diff --git a/ZeroLevel.UnitTests/CollectionsTests.cs b/ZeroLevel.UnitTests/CollectionsTests.cs
new file mode 100644
index 0000000..5af0b42
--- /dev/null
+++ b/ZeroLevel.UnitTests/CollectionsTests.cs
@@ -0,0 +1,62 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System.Linq;
+using ZeroLevel.Services.Collections;
+
+namespace ZeroLevel.UnitTests
+{
+    [TestClass]
+    public class CollectionsTests
+    {
+        [TestMethod]
+        public void RoundRobinCollectionTest()
+        {
+            // Arrange
+            var collection = new RoundRobinCollection<int>();
+            var iter1 = new int[] { 1, 2, 3 };
+            var iter2 = new int[] { 2, 3, 1 };
+            var iter3 = new int[] { 3, 1, 2 };
+
+            var iter11 = new int[] { 1, 3 };
+            var iter12 = new int[] { 3, 1 };
+            // Act
+            collection.Add(1);
+            collection.Add(2);
+            collection.Add(3);
+            // Assert
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter1));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter1));
+            Assert.IsTrue(collection.MoveNext());
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter2));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter2));
+            Assert.IsTrue(collection.MoveNext());
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter3));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter3));
+
+            collection.Remove(2);
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter11));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter11));
+            Assert.IsTrue(collection.MoveNext());
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter12));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GetCurrentSeq().ToArray(), iter12));
+        }
+
+        [TestMethod]
+        public void RoundRobinOverCollectionTest()
+        {
+            var arr = new int[] { 1, 2, 3 };
+            // Arrange
+            var collection = new RoundRobinOverCollection<int>(arr);
+            var iter1 = new int[] { 1, 2, 3 };
+            var iter2 = new int[] { 2, 3, 1 };
+            var iter3 = new int[] { 3, 1, 2 };
+            // Act
+            // Assert
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GenerateSeq().ToArray(), iter1));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GenerateSeq().ToArray(), iter2));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GenerateSeq().ToArray(), iter3));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GenerateSeq().ToArray(), iter1));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GenerateSeq().ToArray(), iter2));
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(collection.GenerateSeq().ToArray(), iter3));
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/MappingTest.cs b/ZeroLevel.UnitTests/MappingTest.cs
index 02fe775..4bd142b 100644
--- a/ZeroLevel.UnitTests/MappingTest.cs
+++ b/ZeroLevel.UnitTests/MappingTest.cs
@@ -3,6 +3,7 @@ using Microsoft.VisualStudio.TestTools.UnitTesting;
 using ZeroLevel.Services.ObjectMapping;
 using ZeroMappingTest.Models;
 using System.Collections.Generic;
+using BusinessApp.DatabaseTest.Model;
 
 namespace ZeroMappingTest
 {
@@ -203,5 +204,51 @@ namespace ZeroMappingTest
             Assert.AreNotSame(mapper1, mapper3);
             Assert.AreNotSame(mapper3, mapper2);
         }
+
+        [TestMethod]
+        public void PocoFieldMapper()
+        {
+            // Arrange
+            var date = new DateTime(2005, 09, 27);
+            var mapper = new TypeMapper(typeof(PocoFields));
+            var obj = new PocoFields { Id = 1000, Date = date, Title = "Caption" };
+
+            // Assert
+            Assert.AreEqual(mapper.EntityType, typeof(PocoFields));
+
+            Assert.IsTrue(mapper.Exists("Id"));
+            Assert.IsTrue(mapper.Exists("Date"));
+            Assert.IsTrue(mapper.Exists("Title"));
+
+            Assert.AreEqual(mapper.Get(obj, "Id"), (long)1000);
+            Assert.AreEqual(mapper.Get(obj, "Date"), date);
+            Assert.AreEqual(mapper.Get(obj, "Title"), "Caption");
+
+            mapper.Set(obj, "Id", 1001);
+            Assert.AreEqual(mapper.Get(obj, "Id"), (long)1001);
+        }
+
+        [TestMethod]
+        public void PocoPropertiesMapper()
+        {
+            // Arrange
+            var date = new DateTime(2005, 09, 27);
+            var mapper = new TypeMapper(typeof(PocoProperties));
+            var obj = new PocoProperties { Id = 1000, Date = date, Title = "Caption" };
+
+            // Assert
+            Assert.AreEqual(mapper.EntityType, typeof(PocoProperties));
+
+            Assert.IsTrue(mapper.Exists("Id"));
+            Assert.IsTrue(mapper.Exists("Date"));
+            Assert.IsTrue(mapper.Exists("Title"));
+
+            Assert.AreEqual(mapper.Get(obj, "Id"), (long)1000);
+            Assert.AreEqual(mapper.Get(obj, "Date"), date);
+            Assert.AreEqual(mapper.Get(obj, "Title"), "Caption");
+
+            mapper.Set(obj, "Id", 1001);
+            Assert.AreEqual(mapper.Get(obj, "Id"), (long)1001);
+        }
     }
 }
diff --git a/ZeroLevel.UnitTests/Models/PocoFields.cs b/ZeroLevel.UnitTests/Models/PocoFields.cs
new file mode 100644
index 0000000..cd52ada
--- /dev/null
+++ b/ZeroLevel.UnitTests/Models/PocoFields.cs
@@ -0,0 +1,11 @@
+using System;
+
+namespace BusinessApp.DatabaseTest.Model
+{
+    public class PocoFields
+    {
+        public long Id;
+        public string Title;
+        public DateTime Date;
+    }
+}
diff --git a/ZeroLevel.UnitTests/Models/PocoProperties.cs b/ZeroLevel.UnitTests/Models/PocoProperties.cs
new file mode 100644
index 0000000..f7d6d66
--- /dev/null
+++ b/ZeroLevel.UnitTests/Models/PocoProperties.cs
@@ -0,0 +1,11 @@
+using System;
+
+namespace BusinessApp.DatabaseTest.Model
+{
+    public class PocoProperties
+    {
+        public long Id { get; set; }
+        public string Title { get; set; }
+        public DateTime Date { get; set; }
+    }
+}
diff --git a/ZeroLevel.UnitTests/Models/Specifications/IsFlagSpecification.cs b/ZeroLevel.UnitTests/Models/Specifications/IsFlagSpecification.cs
new file mode 100644
index 0000000..b33faa5
--- /dev/null
+++ b/ZeroLevel.UnitTests/Models/Specifications/IsFlagSpecification.cs
@@ -0,0 +1,21 @@
+using ZeroLevel.Specification;
+using ZeroSpecificationPatternsTest.Models;
+
+namespace ZeroSpecificationPatternsTest.Specifications
+{
+    public class IsFlagSpecification :
+        BaseSpecification<TestDTO>
+    {
+        private readonly bool _expected;
+
+        public IsFlagSpecification(bool expected)
+        {
+            _expected = expected;
+        }
+
+        public override bool IsSatisfiedBy(TestDTO o)
+        {
+            return o.IsFlag == _expected;
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/Models/Specifications/LongNumberSpecification.cs b/ZeroLevel.UnitTests/Models/Specifications/LongNumberSpecification.cs
new file mode 100644
index 0000000..6b19ec4
--- /dev/null
+++ b/ZeroLevel.UnitTests/Models/Specifications/LongNumberSpecification.cs
@@ -0,0 +1,21 @@
+using ZeroLevel.Specification;
+using ZeroSpecificationPatternsTest.Models;
+
+namespace ZeroSpecificationPatternsTest.Specifications
+{
+    public class LongNumberSpecification :
+        BaseSpecification<TestDTO>
+    {
+        private readonly long _expected;
+
+        public LongNumberSpecification(long expected)
+        {
+            _expected = expected;
+        }
+
+        public override bool IsSatisfiedBy(TestDTO o)
+        {
+            return o.LongNumber == _expected;
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/Models/Specifications/NumberSpecification.cs b/ZeroLevel.UnitTests/Models/Specifications/NumberSpecification.cs
new file mode 100644
index 0000000..60bb3c9
--- /dev/null
+++ b/ZeroLevel.UnitTests/Models/Specifications/NumberSpecification.cs
@@ -0,0 +1,21 @@
+using ZeroLevel.Specification;
+using ZeroSpecificationPatternsTest.Models;
+
+namespace ZeroSpecificationPatternsTest.Specifications
+{
+    public class NumberSpecification :
+        BaseSpecification<TestDTO>
+    {
+        private readonly int _expected;
+
+        public NumberSpecification(int expected)
+        {
+            _expected = expected;
+        }
+
+        public override bool IsSatisfiedBy(TestDTO o)
+        {
+            return o.Number == _expected;
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/Models/Specifications/RealSpecification.cs b/ZeroLevel.UnitTests/Models/Specifications/RealSpecification.cs
new file mode 100644
index 0000000..36f3b7a
--- /dev/null
+++ b/ZeroLevel.UnitTests/Models/Specifications/RealSpecification.cs
@@ -0,0 +1,21 @@
+using ZeroLevel.Specification;
+using ZeroSpecificationPatternsTest.Models;
+
+namespace ZeroSpecificationPatternsTest.Specifications
+{
+    public class RealSpecification :
+        BaseSpecification<TestDTO>
+    {
+        private readonly double _expected;
+
+        public RealSpecification(double expected)
+        {
+            _expected = expected;
+        }
+
+        public override bool IsSatisfiedBy(TestDTO o)
+        {
+            return o.Real == _expected;
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/Models/Specifications/SummarySpecification.cs b/ZeroLevel.UnitTests/Models/Specifications/SummarySpecification.cs
new file mode 100644
index 0000000..a885d20
--- /dev/null
+++ b/ZeroLevel.UnitTests/Models/Specifications/SummarySpecification.cs
@@ -0,0 +1,21 @@
+using ZeroLevel.Specification;
+using ZeroSpecificationPatternsTest.Models;
+
+namespace ZeroSpecificationPatternsTest.Specifications
+{
+    public class SummarySpecification :
+        BaseSpecification<TestDTO>
+    {
+        private readonly string _expected;
+
+        public SummarySpecification(string expected)
+        {
+            _expected = expected;
+        }
+
+        public override bool IsSatisfiedBy(TestDTO o)
+        {
+            return o.Summary == _expected;
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/Models/Specifications/TitleSpecification.cs b/ZeroLevel.UnitTests/Models/Specifications/TitleSpecification.cs
new file mode 100644
index 0000000..8dd05bc
--- /dev/null
+++ b/ZeroLevel.UnitTests/Models/Specifications/TitleSpecification.cs
@@ -0,0 +1,21 @@
+using ZeroLevel.Specification;
+using ZeroSpecificationPatternsTest.Models;
+
+namespace ZeroSpecificationPatternsTest.Specifications
+{
+    public class TitleSpecification :
+        BaseSpecification<TestDTO>
+    {
+        private readonly string _expected;
+
+        public TitleSpecification(string expected)
+        {
+            _expected = expected;
+        }
+
+        public override bool IsSatisfiedBy(TestDTO o)
+        {
+            return o.Title == _expected;
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/Models/TestDTO.cs b/ZeroLevel.UnitTests/Models/TestDTO.cs
new file mode 100644
index 0000000..1c845ae
--- /dev/null
+++ b/ZeroLevel.UnitTests/Models/TestDTO.cs
@@ -0,0 +1,12 @@
+namespace ZeroSpecificationPatternsTest.Models
+{
+    public class TestDTO
+    {
+        public bool IsFlag { get; set; }
+        public int Number;
+        public long LongNumber;
+        public string Title { get; set; }
+        public string Summary;
+        public double Real;
+    }
+}
diff --git a/ZeroLevel.UnitTests/PredicateBuilderTests.cs b/ZeroLevel.UnitTests/PredicateBuilderTests.cs
new file mode 100644
index 0000000..642c7d0
--- /dev/null
+++ b/ZeroLevel.UnitTests/PredicateBuilderTests.cs
@@ -0,0 +1,114 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
+using ZeroLevel.Specification;
+
+namespace ZeroSpecificationPatternsTest
+{
+    [TestClass]
+    public class PredicateBuilderTests
+    {
+        [TestMethod]
+        public void PredicateBuilder_FromExpression_AND()
+        {
+            // Arrange
+            var expression = PredicateBuilder.True<string>();
+            // Act
+            var invoker = expression.
+                And(str => str.Length < 255).
+                And(str => char.IsLetter(str[0])).
+                And(str => char.IsUpper(str[0])).Compile();
+            // Assert
+            Assert.IsFalse(invoker("test"));
+            Assert.IsTrue(invoker("Test"));
+            Assert.IsFalse(invoker("1test"));
+            Assert.IsFalse(invoker("Test" + new string('_', 260)));
+        }
+
+        [TestMethod]
+        public void PredicateBuilder_FromFunc_AND()
+        {
+            // Arrange
+            var func = new Func<string, bool>(str => str.Length < 255);
+            // Act
+            var invoker = func.
+                And(str => str.Length < 255).
+                And(str => Char.IsLetter(str[0])).
+                And(str => Char.IsUpper(str[0])).Compile();
+            // Assert
+            Assert.IsFalse(invoker("test"));
+            Assert.IsTrue(invoker("Test"));
+            Assert.IsFalse(invoker("1test"));
+            Assert.IsFalse(invoker("Test" + new string('_', 260)));
+        }
+
+        [TestMethod]
+        public void PredicateBuilder_FromExpression_OR()
+        {
+            // Arrange
+            var expression = PredicateBuilder.
+                Create<string>(str => str.Equals("hello", StringComparison.OrdinalIgnoreCase));
+            // Act
+            var invoker = expression.
+                Or(str => str.Equals("world", StringComparison.OrdinalIgnoreCase)).
+                Or(str => str.Equals("test", StringComparison.OrdinalIgnoreCase)).
+                Or(str => str.Equals("wow", StringComparison.OrdinalIgnoreCase)).
+                Compile();
+            // Assert
+            Assert.IsTrue(invoker("hello"));
+            Assert.IsTrue(invoker("world"));
+            Assert.IsTrue(invoker("test"));
+            Assert.IsTrue(invoker("wow"));
+            Assert.IsFalse(invoker("Tests"));
+        }
+
+        [TestMethod]
+        public void PredicateBuilder_FromFunc_OR()
+        {
+            // Arrange
+            var func = new Func<string, bool>(str => str.Equals("hello", StringComparison.OrdinalIgnoreCase));
+            // Act
+            var invoker = func.
+                Or(str => str.Equals("world", StringComparison.OrdinalIgnoreCase)).
+                Or(str => str.Equals("test", StringComparison.OrdinalIgnoreCase)).
+                Or(str => str.Equals("wow", StringComparison.OrdinalIgnoreCase)).
+                Compile();
+            // Assert
+            Assert.IsTrue(invoker("hello"));
+            Assert.IsTrue(invoker("world"));
+            Assert.IsTrue(invoker("test"));
+            Assert.IsTrue(invoker("wow"));
+            Assert.IsFalse(invoker("Tests"));
+        }
+
+        [TestMethod]
+        public void PredicateBuilder_FromExpression_NOT()
+        {
+            // Arrange
+            var expression = PredicateBuilder.
+                Create<int>(i => i < 100 && i > 0);
+            // Act
+            var invoker = expression.Not().
+                Compile();
+            // Assert
+            Assert.IsFalse(invoker(1));
+            Assert.IsFalse(invoker(50));
+            Assert.IsTrue(invoker(100));
+            Assert.IsTrue(invoker(0));
+        }
+
+        [TestMethod]
+        public void PredicateBuilder_FromFunc_NOT()
+        {
+            // Arrange
+            var expression = new Func<int, bool>(i => i < 100 && i > 0);
+            // Act
+            var invoker = expression.Not().
+                Compile();
+            // Assert
+            Assert.IsFalse(invoker(1));
+            Assert.IsFalse(invoker(50));
+            Assert.IsTrue(invoker(100));
+            Assert.IsTrue(invoker(0));
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/QueriesTests.cs b/ZeroLevel.UnitTests/QueriesTests.cs
new file mode 100644
index 0000000..4d3c86f
--- /dev/null
+++ b/ZeroLevel.UnitTests/QueriesTests.cs
@@ -0,0 +1,190 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using ZeroLevel.Patterns.Queries;
+using ZeroSpecificationPatternsTest.Models;
+
+namespace ZeroSpecificationPatternsTest
+{
+    /// <summary>
+    /// Summary description for UnitTest1
+    /// </summary>
+    [TestClass]
+    public class QueriesTests
+    {
+        private static bool TestDTOEqual(TestDTO left, TestDTO right)
+        {
+            if (left == null && right == null) return true;
+            if (left == null || right == null) return false;
+            if (left.IsFlag != right.IsFlag) return false;
+            if (left.LongNumber != right.LongNumber) return false;
+            if (left.Number != right.Number) return false;
+            if (left.Real != right.Real) return false;
+            if (string.Compare(left.Summary, right.Summary, StringComparison.Ordinal) != 0) return false;
+            if (string.Compare(left.Title, right.Title, StringComparison.Ordinal) != 0) return false;
+            return true;
+        }
+
+        [TestMethod]
+        public void MemoryStoragePostTest()
+        {
+            var storage = new MemoryStorage<TestDTO>();
+            var a1 = storage.Post(new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = 100,
+                Number = 1000,
+                Real = 1000.0001,
+                Summary = "Summary #1",
+                Title = "Title #1"
+            });
+            var a2 = storage.Post(new TestDTO
+            {
+                IsFlag = true,
+                LongNumber = 0,
+                Number = -500,
+                Real = 500.005,
+                Summary = "Summary #2",
+                Title = "Title #2"
+            });
+            var a3 = storage.Post(new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = -1,
+                Number = 500,
+                Real = -0.0001,
+                Summary = "Summary #3",
+                Title = "Title #3"
+            });
+            Assert.IsTrue(a1.Success);
+            Assert.AreEqual<long>(a1.Count, 1);
+            Assert.IsTrue(a2.Success);
+            Assert.AreEqual<long>(a2.Count, 1);
+            Assert.IsTrue(a3.Success);
+            Assert.AreEqual<long>(a3.Count, 1);
+        }
+
+        [TestMethod]
+        public void MemoryStorageGetAllTest()
+        {
+            var set = new List<TestDTO>();
+            set.Add(new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = 100,
+                Number = 1000,
+                Real = 1000.0001,
+                Summary = "Summary #1",
+                Title = "Title #1"
+            });
+            set.Add(new TestDTO
+            {
+                IsFlag = true,
+                LongNumber = 0,
+                Number = -500,
+                Real = 500.005,
+                Summary = "Summary #2",
+                Title = "Title #2"
+            });
+            set.Add(new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = -1,
+                Number = 500,
+                Real = -0.0001,
+                Summary = "Summary #3",
+                Title = "Title #3"
+            });
+            var storage = new MemoryStorage<TestDTO>();
+            foreach (var i in set)
+            {
+                var ar = storage.Post(i);
+                Assert.IsTrue(ar.Success);
+                Assert.AreEqual<long>(ar.Count, 1);
+            }
+            // Test equals set and storage data
+            foreach (var i in storage.Get())
+            {
+                Assert.IsTrue(set.Exists(dto => TestDTOEqual(i, dto)));
+            }
+            // Modify originals
+            foreach (var i in set)
+            {
+                i.Title = "###";
+            }
+            // Test independences storage from original
+            foreach (var i in storage.Get())
+            {
+                Assert.IsFalse(set.Exists(dto => TestDTOEqual(i, dto)));
+            }
+        }
+
+
+        [TestMethod]
+        public void MemoryStorageGetByTest()
+        {
+            var set = new List<TestDTO>();
+            set.Add(new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = 100,
+                Number = 1000,
+                Real = 1000.0001,
+                Summary = "Summary #1",
+                Title = "Title #1"
+            });
+            set.Add(new TestDTO
+            {
+                IsFlag = true,
+                LongNumber = 0,
+                Number = -500,
+                Real = 500.005,
+                Summary = "Summary #2",
+                Title = "Title #2"
+            });
+            set.Add(new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = -1,
+                Number = 500,
+                Real = -0.0001,
+                Summary = "Summary #3",
+                Title = "Title #3"
+            });
+            var storage = new MemoryStorage<TestDTO>();
+            foreach (var i in set)
+            {
+                var ar = storage.Post(i);
+                Assert.IsTrue(ar.Success);
+                Assert.AreEqual<long>(ar.Count, 1);
+            }
+            // Test equals set and storage data
+            foreach (var i in storage.Get())
+            {
+                Assert.IsTrue(set.Exists(dto => TestDTOEqual(i, dto)));
+            }
+            foreach (var i in storage.Get(Query.ALL()))
+            {
+                Assert.IsTrue(set.Exists(dto => TestDTOEqual(i, dto)));
+            }
+            var result_eq = storage.Get(Query.EQ("Title", "Title #1"));
+            Assert.AreEqual<int>(result_eq.Count(), 1);
+            Assert.IsTrue(TestDTOEqual(set[0], result_eq.First()));
+
+            var result_neq = storage.Get(Query.NEQ("Title", "Title #1"));
+            Assert.AreEqual<int>(result_neq.Count(), 2);
+            Assert.IsTrue(TestDTOEqual(set[1], result_neq.First()));
+            Assert.IsTrue(TestDTOEqual(set[2], result_neq.Skip(1).First()));
+
+            var result_gt = storage.Get(Query.GT("Number", 1));
+            Assert.AreEqual<int>(result_gt.Count(), 2);
+            Assert.IsTrue(TestDTOEqual(set[0], result_gt.First()));
+            Assert.IsTrue(TestDTOEqual(set[2], result_gt.Skip(1).First()));
+
+            var result_lt = storage.Get(Query.LT("Number", 1));
+            Assert.AreEqual<int>(result_lt.Count(), 1);
+            Assert.IsTrue(TestDTOEqual(set[1], result_lt.First()));
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/SpecificationPatternTest.cs b/ZeroLevel.UnitTests/SpecificationPatternTest.cs
new file mode 100644
index 0000000..17f84a9
--- /dev/null
+++ b/ZeroLevel.UnitTests/SpecificationPatternTest.cs
@@ -0,0 +1,419 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using ZeroLevel.Specification;
+using ZeroSpecificationPatternsTest.Models;
+using ZeroSpecificationPatternsTest.Specifications;
+
+namespace ZeroSpecificationPatternsTest
+{
+    /// <summary>
+    /// Summary description for SpecificationPatternTest
+    /// </summary>
+    [TestClass]
+    public class SpecificationPatternTest
+    {
+        [TestMethod]
+        public void SimpleSpecificationTest()
+        {
+            // Assert
+            var dto_one = new TestDTO
+            {
+                IsFlag = true,
+                LongNumber = 100,
+                Number = 1000,
+                Real = 3.141,
+                Summary = "Summary",
+                Title = "Title"
+            };
+            var dto_two = new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = 0,
+                Number = 0,
+                Real = 0,
+                Summary = string.Empty,
+                Title = string.Empty
+            };
+            var flag_spec_true = new IsFlagSpecification(true);
+            var flag_spec_false = new IsFlagSpecification(false);
+
+            var long_specification_full = new LongNumberSpecification(100);
+            var long_specification_empty = new LongNumberSpecification(0);
+
+            var number_specification_full = new NumberSpecification(1000);
+            var number_specification_empty = new NumberSpecification(0);
+
+            var real_specification_full = new RealSpecification(3.141);
+            var real_specification_empty = new RealSpecification(0);
+
+            var summary_specification_full = new SummarySpecification("Summary");
+            var summary_specification_empty = new SummarySpecification(string.Empty);
+
+            var title_specification_full = new TitleSpecification("Title");
+            var title_specification_empty = new TitleSpecification(string.Empty);
+
+            // Assert
+            Assert.IsTrue(flag_spec_true.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(flag_spec_false.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(flag_spec_false.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(flag_spec_true.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(long_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(long_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(long_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(long_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(number_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(number_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(number_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(number_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(real_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(real_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(real_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(real_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(summary_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(summary_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(summary_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(summary_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(title_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(title_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(title_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(title_specification_full.IsSatisfiedBy(dto_two));
+        }
+
+        [TestMethod]
+        public void NotSpecificationTest()
+        {
+            // Assert
+            var dto_one = new TestDTO
+            {
+                IsFlag = true,
+                LongNumber = 100,
+                Number = 1000,
+                Real = 3.141,
+                Summary = "Summary",
+                Title = "Title"
+            };
+            var dto_two = new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = 0,
+                Number = 0,
+                Real = 0,
+                Summary = string.Empty,
+                Title = string.Empty
+            };
+            var flag_spec_true = new IsFlagSpecification(true).Not();
+            var flag_spec_false = new IsFlagSpecification(false).Not();
+
+            var long_specification_full = new LongNumberSpecification(100).Not();
+            var long_specification_empty = new LongNumberSpecification(0).Not();
+
+            var number_specification_full = new NumberSpecification(1000).Not();
+            var number_specification_empty = new NumberSpecification(0).Not();
+
+            var real_specification_full = new RealSpecification(3.141).Not();
+            var real_specification_empty = new RealSpecification(0).Not();
+
+            var summary_specification_full = new SummarySpecification("Summary").Not();
+            var summary_specification_empty = new SummarySpecification(string.Empty).Not();
+
+            var title_specification_full = new TitleSpecification("Title").Not();
+            var title_specification_empty = new TitleSpecification(string.Empty).Not();
+
+            // Assert
+            Assert.IsFalse(flag_spec_true.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(flag_spec_false.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(flag_spec_false.IsSatisfiedBy(dto_two));
+            Assert.IsTrue(flag_spec_true.IsSatisfiedBy(dto_two));
+
+            Assert.IsFalse(long_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(long_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(long_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsTrue(long_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsFalse(number_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(number_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(number_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsTrue(number_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsFalse(real_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(real_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(real_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsTrue(real_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsFalse(summary_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(summary_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(summary_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsTrue(summary_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsFalse(title_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(title_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(title_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsTrue(title_specification_full.IsSatisfiedBy(dto_two));
+        }
+
+        [TestMethod]
+        public void ComposedAndSpecificationTest()
+        {
+            // Assert
+            var dto_one = new TestDTO
+            {
+                IsFlag = true,
+                LongNumber = 100,
+                Number = 1000,
+                Real = 3.141,
+                Summary = "Summary",
+                Title = "Title"
+            };
+            var dto_two = new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = 0,
+                Number = 0,
+                Real = 0,
+                Summary = string.Empty,
+                Title = string.Empty
+            };
+            var flag_spec_true = new IsFlagSpecification(true);
+            var flag_spec_false = new IsFlagSpecification(false);
+
+            var long_specification_full = new LongNumberSpecification(100);
+            var long_specification_empty = new LongNumberSpecification(0);
+
+            var number_specification_full = new NumberSpecification(1000);
+            var number_specification_empty = new NumberSpecification(0);
+
+            var real_specification_full = new RealSpecification(3.141);
+            var real_specification_empty = new RealSpecification(0);
+
+            var summary_specification_full = new SummarySpecification("Summary");
+            var summary_specification_empty = new SummarySpecification(string.Empty);
+
+            var title_specification_full = new TitleSpecification("Title");
+            var title_specification_empty = new TitleSpecification(string.Empty);
+
+            // Act
+
+            var composed_full = flag_spec_true.
+                And(long_specification_full).
+                And(number_specification_full).
+                And(real_specification_full).
+                And(summary_specification_full).
+                And(title_specification_full);
+
+            var composed_empty = flag_spec_false.
+                And(long_specification_empty).
+                And(number_specification_empty).
+                And(real_specification_empty).
+                And(summary_specification_empty).
+                And(title_specification_empty);
+
+            // Assert
+            Assert.IsTrue(composed_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(composed_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(composed_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(composed_full.IsSatisfiedBy(dto_two));
+        }
+
+        [TestMethod]
+        public void ComposedOrSpecificationTest()
+        {
+            // Assert
+            var dto_one = new TestDTO
+            {
+                IsFlag = true,
+                LongNumber = 100,
+                Number = 1000,
+                Real = 3.141,
+                Summary = "Summary",
+                Title = "Title"
+            };
+            var dto_two = new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = 0,
+                Number = 0,
+                Real = 0,
+                Summary = string.Empty,
+                Title = string.Empty
+            };
+            var flag_spec_true = new IsFlagSpecification(true);
+            var flag_spec_false = new IsFlagSpecification(false);
+
+            var long_specification_full = new LongNumberSpecification(100);
+            var long_specification_empty = new LongNumberSpecification(0);
+
+            var number_specification_full = new NumberSpecification(1000);
+            var number_specification_empty = new NumberSpecification(0);
+
+            var real_specification_full = new RealSpecification(3.141);
+            var real_specification_empty = new RealSpecification(0);
+
+            var summary_specification_full = new SummarySpecification("Summary");
+            var summary_specification_empty = new SummarySpecification(string.Empty);
+
+            var title_specification_full = new TitleSpecification("Title");
+            var title_specification_empty = new TitleSpecification(string.Empty);
+
+            // Act
+
+            var composed_full = flag_spec_false.
+                Or(long_specification_full).
+                Or(number_specification_full).
+                Or(real_specification_full).
+                Or(summary_specification_full).
+                Or(title_specification_full);
+
+            var composed_empty = flag_spec_true.
+                Or(long_specification_empty).
+                Or(number_specification_empty).
+                Or(real_specification_empty).
+                Or(summary_specification_empty).
+                Or(title_specification_empty);
+
+            // Assert
+            Assert.IsTrue(composed_full.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(composed_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(composed_empty.IsSatisfiedBy(dto_two));
+            Assert.IsTrue(composed_full.IsSatisfiedBy(dto_two));
+        }
+
+        [TestMethod]
+        public void ExpressionSpecificationTest()
+        {
+            // Assert
+            var dto_one = new TestDTO
+            {
+                IsFlag = true,
+                LongNumber = 100,
+                Number = 1000,
+                Real = 3.141,
+                Summary = "Summary",
+                Title = "Title"
+            };
+            var dto_two = new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = 0,
+                Number = 0,
+                Real = 0,
+                Summary = string.Empty,
+                Title = string.Empty
+            };
+            var flag_spec_true = new ExpressionSpecification<TestDTO>(o=>o.IsFlag == true);
+            var flag_spec_false = new ExpressionSpecification<TestDTO>(o => o.IsFlag == false);
+
+            var long_specification_full = new ExpressionSpecification<TestDTO>(o => o.LongNumber == 100);
+            var long_specification_empty = new ExpressionSpecification<TestDTO>(o => o.LongNumber == 0);
+
+            var number_specification_full = new ExpressionSpecification<TestDTO>(o => o.Number == 1000);
+            var number_specification_empty = new ExpressionSpecification<TestDTO>(o => o.Number == 0);
+
+            var real_specification_full = new ExpressionSpecification<TestDTO>(o => o.Real == 3.141);
+            var real_specification_empty = new ExpressionSpecification<TestDTO>(o => o.Real == 0);
+
+            var summary_specification_full = new ExpressionSpecification<TestDTO>(o => o.Summary == "Summary");
+            var summary_specification_empty = new ExpressionSpecification<TestDTO>(o => o.Summary == string.Empty);
+
+            var title_specification_full = new ExpressionSpecification<TestDTO>(o => o.Title == "Title");
+            var title_specification_empty = new ExpressionSpecification<TestDTO>(o => o.Title == string.Empty);
+
+            // Assert
+            Assert.IsTrue(flag_spec_true.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(flag_spec_false.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(flag_spec_false.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(flag_spec_true.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(long_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(long_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(long_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(long_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(number_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(number_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(number_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(number_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(real_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(real_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(real_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(real_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(summary_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(summary_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(summary_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(summary_specification_full.IsSatisfiedBy(dto_two));
+
+            Assert.IsTrue(title_specification_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(title_specification_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(title_specification_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(title_specification_full.IsSatisfiedBy(dto_two));
+        }
+
+        [TestMethod]
+        public void ComposedExpressionSpecificationTest()
+        {
+            // Assert
+            var dto_one = new TestDTO
+            {
+                IsFlag = true,
+                LongNumber = 100,
+                Number = 1000,
+                Real = 3.141,
+                Summary = "Summary",
+                Title = "Title"
+            };
+            var dto_two = new TestDTO
+            {
+                IsFlag = false,
+                LongNumber = 0,
+                Number = 0,
+                Real = 0,
+                Summary = string.Empty,
+                Title = string.Empty
+            };
+            var flag_spec_true = new ExpressionSpecification<TestDTO>(o => o.IsFlag == true);
+            var flag_spec_false = new ExpressionSpecification<TestDTO>(o => o.IsFlag == false);
+
+            var long_specification_full = new ExpressionSpecification<TestDTO>(o => o.LongNumber == 100);
+            var long_specification_empty = new ExpressionSpecification<TestDTO>(o => o.LongNumber == 0);
+
+            var number_specification_full = new ExpressionSpecification<TestDTO>(o => o.Number == 1000);
+            var number_specification_empty = new ExpressionSpecification<TestDTO>(o => o.Number == 0);
+
+            var real_specification_full = new ExpressionSpecification<TestDTO>(o => o.Real == 3.141);
+            var real_specification_empty = new ExpressionSpecification<TestDTO>(o => o.Real == 0);
+
+            var summary_specification_full = new ExpressionSpecification<TestDTO>(o => o.Summary == "Summary");
+            var summary_specification_empty = new ExpressionSpecification<TestDTO>(o => o.Summary == string.Empty);
+
+            var title_specification_full = new ExpressionSpecification<TestDTO>(o => o.Title == "Title");
+            var title_specification_empty = new ExpressionSpecification<TestDTO>(o => o.Title == string.Empty);
+
+            // Act
+
+            var composed_full = flag_spec_true.
+                And(long_specification_full).
+                And(number_specification_full).
+                And(real_specification_full).
+                And(summary_specification_full).
+                And(title_specification_full);
+
+            var composed_empty = flag_spec_false.
+                And(long_specification_empty).
+                And(number_specification_empty).
+                And(real_specification_empty).
+                And(summary_specification_empty).
+                And(title_specification_empty);
+
+            // Assert
+            Assert.IsTrue(composed_full.IsSatisfiedBy(dto_one));
+            Assert.IsFalse(composed_empty.IsSatisfiedBy(dto_one));
+            Assert.IsTrue(composed_empty.IsSatisfiedBy(dto_two));
+            Assert.IsFalse(composed_full.IsSatisfiedBy(dto_two));
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/ZeroLevel.UnitTests.csproj b/ZeroLevel.UnitTests/ZeroLevel.UnitTests.csproj
index 12a3835..c4739c4 100644
--- a/ZeroLevel.UnitTests/ZeroLevel.UnitTests.csproj
+++ b/ZeroLevel.UnitTests/ZeroLevel.UnitTests.csproj
@@ -50,15 +50,28 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="ArrayToolsTest.cs" />
+    <Compile Include="CollectionsTests.cs" />
     <Compile Include="InvokingTest.cs" />
     <Compile Include="MappingTest.cs" />
     <Compile Include="Models\BaseClass.cs" />
     <Compile Include="Models\BaseFakeClass.cs" />
     <Compile Include="Models\ChildClass.cs" />
     <Compile Include="Models\FakeClass.cs" />
+    <Compile Include="Models\PocoFields.cs" />
+    <Compile Include="Models\PocoProperties.cs" />
+    <Compile Include="Models\Specifications\IsFlagSpecification.cs" />
+    <Compile Include="Models\Specifications\LongNumberSpecification.cs" />
+    <Compile Include="Models\Specifications\NumberSpecification.cs" />
+    <Compile Include="Models\Specifications\RealSpecification.cs" />
+    <Compile Include="Models\Specifications\SummarySpecification.cs" />
+    <Compile Include="Models\Specifications\TitleSpecification.cs" />
     <Compile Include="Models\StaticFakeClass.cs" />
+    <Compile Include="Models\TestDTO.cs" />
+    <Compile Include="PredicateBuilderTests.cs" />
+    <Compile Include="QueriesTests.cs" />
     <Compile Include="SerializationTests.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="SpecificationPatternTest.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="packages.config" />