diff --git a/test/Services/UnitTest/Ordering/Application/ExistingCommandBehaviorTest.cs b/test/Services/UnitTest/Ordering/Application/ExistingCommandBehaviorTest.cs
new file mode 100644
index 000000000..d3a736a3f
--- /dev/null
+++ b/test/Services/UnitTest/Ordering/Application/ExistingCommandBehaviorTest.cs
@@ -0,0 +1,92 @@
+using System;
+using System.Reflection;
+using System.Threading;
+using System.Threading.Tasks;
+using Autofac;
+using MediatR;
+using Microsoft.eShopOnContainers.Services.Ordering.API.Application.Commands;
+using Microsoft.eShopOnContainers.Services.Ordering.Infrastructure.Idempotency;
+using Moq;
+using Ordering.API.Infrastructure.Behaviors;
+using Xunit;
+
+namespace UnitTest.Ordering.Application
+{
+    public class ExistingCommandBehaviorTest
+    {
+        private readonly Mock<IRequestManager> _requestManager;
+        private readonly Mock<IRequestHandler<CreateOrderCommand, bool>> _commandHandler;
+
+        public ExistingCommandBehaviorTest()
+        {
+            _requestManager = new Mock<IRequestManager>();
+            _commandHandler = new Mock<IRequestHandler<CreateOrderCommand, bool>>();
+        }
+
+        private ContainerBuilder PrepareContainerBuilder()
+        {
+            var builder = new ContainerBuilder();
+            builder.RegisterAssemblyTypes(typeof(IMediator).GetTypeInfo().Assembly)
+                .AsImplementedInterfaces();
+
+            builder.Register<ServiceFactory>(context =>
+            {
+                var componentContext = context.Resolve<IComponentContext>();
+                return t => { object o; return componentContext.TryResolve(t, out o) ? o : null; };
+            });
+           
+            builder.RegisterInstance(_requestManager.Object).AsImplementedInterfaces();
+            builder.RegisterInstance(_commandHandler.Object).AsImplementedInterfaces();
+
+            builder.RegisterGeneric(typeof(ExistingCommandBehavior<,>)).As(typeof(IPipelineBehavior<,>));
+            return builder;
+        }
+
+        [Fact]
+        public async Task Handler_sends_command_when_no_order_exists()
+        {
+            //Arrange
+            var command = new CreateOrderCommand();
+            _requestManager.Setup(x => x.ExistAsync(It.IsAny<Guid>()))
+                .Returns(Task.FromResult(false));
+            
+            var builder = PrepareContainerBuilder();
+            var container = builder.Build();
+
+            var mediator = container.Resolve<IMediator>();
+
+            //Act
+            await mediator.Send(command);
+
+            //Assert
+            _commandHandler.Verify(x => x.Handle(It.IsAny<CreateOrderCommand>(), It.IsAny<CancellationToken>()), Times.Once);
+        }
+
+        [Fact]
+        public async Task Handler_sends_no_command_and_returns_defined_response_when_order_already_exists()
+        {
+            //Arrange
+            var command = new CreateOrderCommand();
+            var existingCommandResponse = new Mock<IRequestHandler<ExistingCommandResponse<CreateOrderCommand, bool>.ExistingCommand, bool>>();
+            existingCommandResponse.Setup(x => x.Handle(It.IsAny<ExistingCommandResponse<CreateOrderCommand, bool>.ExistingCommand>(), It.IsAny<CancellationToken>()))
+                .Returns(Task.FromResult(true));
+
+            _requestManager.Setup(x => x.ExistAsync(It.IsAny<Guid>()))
+                .Returns(Task.FromResult(true));
+
+            var builder = PrepareContainerBuilder();
+            builder.RegisterInstance(existingCommandResponse.Object).AsImplementedInterfaces();
+            var container = builder.Build();
+
+            var mediator = container.Resolve<IMediator>();
+
+            //Act
+            var response = await mediator.Send(command);
+
+            //Assert
+            Assert.True(response);
+            existingCommandResponse.Verify(x => x.Handle(It.IsAny<ExistingCommandResponse<CreateOrderCommand, bool>.ExistingCommand>(), It.IsAny<CancellationToken>()), Times.Once);
+            _commandHandler.Verify(x => x.Handle(It.IsAny<CreateOrderCommand>(), It.IsAny<CancellationToken>()), Times.Never);
+        }
+    }
+}
diff --git a/test/Services/UnitTest/Ordering/Application/ValidatorBehaviorTest.cs b/test/Services/UnitTest/Ordering/Application/ValidatorBehaviorTest.cs
new file mode 100644
index 000000000..b45df5324
--- /dev/null
+++ b/test/Services/UnitTest/Ordering/Application/ValidatorBehaviorTest.cs
@@ -0,0 +1,52 @@
+using System.Reflection;
+using System.Threading.Tasks;
+using Autofac;
+using FluentValidation;
+using FluentValidation.Results;
+using MediatR;
+using Microsoft.eShopOnContainers.Services.Ordering.API.Application.Commands;
+using Moq;
+using Ordering.API.Infrastructure.Behaviors;
+using Ordering.Domain.Exceptions;
+using Xunit;
+
+namespace UnitTest.Ordering.Application
+{
+    public class ValidatorBehaviorTest
+    {
+        private ContainerBuilder PrepareContainerBuilder()
+        {
+            var builder = new ContainerBuilder();
+            builder.RegisterAssemblyTypes(typeof(IMediator).GetTypeInfo().Assembly)
+                .AsImplementedInterfaces();
+
+            builder.Register<ServiceFactory>(context =>
+            {
+                var componentContext = context.Resolve<IComponentContext>();
+                return t => { object o; return componentContext.TryResolve(t, out o) ? o : null; };
+            });
+
+            builder.RegisterGeneric(typeof(ValidatorBehavior<,>)).As(typeof(IPipelineBehavior<,>));
+            return builder;
+        }
+
+        [Fact]
+        public async Task Handler_throws_when_validation_fails()
+        {
+            //Arrange
+            var command = new CreateOrderCommand();
+            var validator = new Mock<IValidator<CreateOrderCommand>>();
+            validator.Setup(x => x.Validate(It.IsAny<CreateOrderCommand>()))
+                .Returns(new ValidationResult(new[] {new ValidationFailure("property", "error")}));
+            
+            var builder = PrepareContainerBuilder();
+            builder.RegisterInstance(validator.Object).AsImplementedInterfaces();
+            var container = builder.Build();
+
+            var mediator = container.Resolve<IMediator>();
+            
+            //Assert
+            await Assert.ThrowsAsync<OrderingDomainException>(async () => await mediator.Send(command));
+        }
+    }
+}
\ No newline at end of file
diff --git a/test/Services/UnitTest/UnitTest.csproj b/test/Services/UnitTest/UnitTest.csproj
index 02cf8cae6..bcf5dfb23 100644
--- a/test/Services/UnitTest/UnitTest.csproj
+++ b/test/Services/UnitTest/UnitTest.csproj
@@ -20,6 +20,7 @@
   </ItemGroup>
 
   <ItemGroup>
+    <PackageReference Include="Autofac" Version="4.8.1" />
     <PackageReference Include="Microsoft.DotNet.InternalAbstractions" Version="1.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.7.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.3.1" />