diff --git a/UnitTesting/GlobalUsings.cs b/UnitTesting/GlobalUsings.cs
new file mode 100644
index 0000000..cefced4
--- /dev/null
+++ b/UnitTesting/GlobalUsings.cs
@@ -0,0 +1 @@
+global using NUnit.Framework;
\ No newline at end of file
diff --git a/UnitTesting/TirePressureMonitoringSystem.Test/AlarmTest.cs b/UnitTesting/TirePressureMonitoringSystem.Test/AlarmTest.cs
new file mode 100644
index 0000000..bbc3f36
--- /dev/null
+++ b/UnitTesting/TirePressureMonitoringSystem.Test/AlarmTest.cs
@@ -0,0 +1,47 @@
+using Moq;
+using TDDMicroExercises.TirePressureMonitoringSystem;
+
+namespace UnitTesting.TirePressureMonitoringSystem.Test
+{
+    //Testing the Alarm class using mock implementation of Sensor
+
+    [TestFixture]
+    public class AlarmTest
+    {
+        [Test]
+        public void Check_WhetherAlarmOnWhenPressureBelowLowThreshold()
+        {
+            var mockSensor = new Mock<ISensor>();
+            mockSensor.Setup(sensor => sensor.PopNextPressurePsiValue()).Returns(15);
+            var alarm = new Alarm(mockSensor.Object);
+
+            alarm.Check();
+
+            Assert.IsTrue(alarm.AlarmOn);
+        }
+
+        [Test]
+        public void Check_WhetherAlarmOnWhenPressureAboveHighThreshold()
+        {
+            var mockSensor = new Mock<ISensor>();
+            mockSensor.Setup(sensor => sensor.PopNextPressurePsiValue()).Returns(22);
+            var alarm = new Alarm(mockSensor.Object);
+
+            alarm.Check();
+
+            Assert.IsTrue(alarm.AlarmOn);
+        }
+
+        [Test]
+        public void Check_WhetherAlarmOffWhenPressureWithinThresholdRange()
+        {
+            var mockSensor = new Mock<ISensor>();
+            mockSensor.Setup(sensor => sensor.PopNextPressurePsiValue()).Returns(18);
+            var alarm = new Alarm(mockSensor.Object);
+
+            alarm.Check();
+
+            Assert.IsFalse(alarm.AlarmOn);
+        }
+    }
+}
\ No newline at end of file
diff --git a/UnitTesting/TurnTicketDispenser.Test/TicketDispenserTest.cs b/UnitTesting/TurnTicketDispenser.Test/TicketDispenserTest.cs
new file mode 100644
index 0000000..c1b0f65
--- /dev/null
+++ b/UnitTesting/TurnTicketDispenser.Test/TicketDispenserTest.cs
@@ -0,0 +1,76 @@
+using Moq;
+using TDDMicroExercises.TurnTicketDispenser;
+
+namespace UnitTesting.TurnTicketDispenser.Test
+{
+    //Testing the TicketDispenser class using mock implementation of ITurnNumberSource
+
+    [TestFixture]
+    public class TicketDispenserTest
+    {
+        [Test]
+        public void Dispenser_ShouldReturnNonNegativeTicketTurnNumber()
+        {
+            var mockTurnNumberSequence = new Mock<ITurnNumberSequence>();
+            mockTurnNumberSequence.Setup(seq => seq.GetNextTurnNumber()).Returns(1);
+
+            var dispenser = new TicketDispenser(mockTurnNumberSequence.Object);
+            var ticket = dispenser.GetTurnTicket();
+
+            Assert.That(ticket.TurnNumber, Is.GreaterThanOrEqualTo(0));
+        }
+
+        [Test]
+        public void Dispenser_ShouldReturnSubsequentTicketTurnNumberEveryTime()
+        {
+            var mockTurnNumberSequence = new Mock<ITurnNumberSequence>();
+            mockTurnNumberSequence.SetupSequence(seq => seq.GetNextTurnNumber())
+                .Returns(1)
+                .Returns(2)
+                .Returns(3);
+
+            var ticketDispenser = new TicketDispenser(mockTurnNumberSequence.Object);
+
+            var ticket1 = ticketDispenser.GetTurnTicket();
+            var ticket2 = ticketDispenser.GetTurnTicket();
+            var ticket3 = ticketDispenser.GetTurnTicket();
+
+            Assert.AreEqual(1, ticket1.TurnNumber);
+            Assert.AreEqual(2, ticket2.TurnNumber);
+            Assert.AreEqual(3, ticket3.TurnNumber);
+        }
+
+        [Test]
+        public void MultipleDispensers_ShouldReturnSubsequentTicketTurnNumber()
+        {
+            var mockTurnNumberSequence = new Mock<ITurnNumberSequence>();
+            mockTurnNumberSequence.SetupSequence(seq => seq.GetNextTurnNumber())
+                .Returns(11)
+                .Returns(12);
+
+            var dispenser1 = new TicketDispenser(mockTurnNumberSequence.Object);
+            var dispenser2 = new TicketDispenser(mockTurnNumberSequence.Object);
+
+            var ticket1 = dispenser1.GetTurnTicket();
+            var ticket2 = dispenser2.GetTurnTicket();
+
+            Assert.AreEqual(11, ticket1.TurnNumber);
+            Assert.AreEqual(12, ticket2.TurnNumber);
+        }
+
+        [Test]
+        public void MultipleDispensers_ShouldReturnDistinctTicketTurnNumber()
+        {
+            var turnNumberSequence = new TurnNumberSequence();
+            var dispenserFactory = new TicketDispenserFactory(turnNumberSequence);
+
+            var dispenser1 = dispenserFactory.CreateTicketDispenser();
+            var dispenser2 = dispenserFactory.CreateTicketDispenser();
+
+            var ticket1 = dispenser1.GetTurnTicket();
+            var ticket2 = dispenser2.GetTurnTicket();
+
+            Assert.That(ticket1.TurnNumber, Is.Not.EqualTo(ticket2.TurnNumber));
+        }
+    }
+}
diff --git a/UnitTesting/UnitTesting.csproj b/UnitTesting/UnitTesting.csproj
new file mode 100644
index 0000000..debc0da
--- /dev/null
+++ b/UnitTesting/UnitTesting.csproj
@@ -0,0 +1,25 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+
+    <IsPackable>false</IsPackable>
+    <IsTestProject>true</IsTestProject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.5.0" />
+    <PackageReference Include="Moq" Version="4.20.69" />
+    <PackageReference Include="NUnit" Version="3.13.3" />
+    <PackageReference Include="NUnit3TestAdapter" Version="4.4.2" />
+    <PackageReference Include="NUnit.Analyzers" Version="3.6.1" />
+    <PackageReference Include="coverlet.collector" Version="3.2.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\src\TDDMicroExercises.csproj" />
+  </ItemGroup>
+
+</Project>
diff --git a/src/TDDMicroExercises.csproj b/src/TDDMicroExercises.csproj
index 3ae5879..e4edf20 100644
--- a/src/TDDMicroExercises.csproj
+++ b/src/TDDMicroExercises.csproj
@@ -1,5 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="4.0">
+  <Import Project="packages\Microsoft.NET.Test.Sdk.17.7.1\build\net462\Microsoft.NET.Test.Sdk.props" Condition="Exists('packages\Microsoft.NET.Test.Sdk.17.7.1\build\net462\Microsoft.NET.Test.Sdk.props')" />
+  <Import Project="packages\Microsoft.CodeCoverage.17.7.1\build\netstandard2.0\Microsoft.CodeCoverage.props" Condition="Exists('packages\Microsoft.CodeCoverage.17.7.1\build\netstandard2.0\Microsoft.CodeCoverage.props')" />
+  <Import Project="packages\NUnit3TestAdapter.3.17.0\build\net35\NUnit3TestAdapter.props" Condition="Exists('packages\NUnit3TestAdapter.3.17.0\build\net35\NUnit3TestAdapter.props')" />
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
     <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
@@ -10,11 +13,14 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>TDDMicroExercises</RootNamespace>
     <AssemblyName>TDDMicroExercises</AssemblyName>
-    <TargetFrameworkVersion>v4.5.2</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.8</TargetFrameworkVersion>
     <FileUpgradeFlags>
     </FileUpgradeFlags>
     <OldToolsVersion>2.0</OldToolsVersion>
     <UpgradeBackupLocation />
+    <TargetFrameworkProfile />
+    <NuGetPackageImportStamp>
+    </NuGetPackageImportStamp>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
     <DebugSymbols>true</DebugSymbols>
@@ -34,7 +40,23 @@
     <WarningLevel>4</WarningLevel>
   </PropertyGroup>
   <ItemGroup>
+    <Reference Include="Castle.Core, Version=5.0.0.0, Culture=neutral, PublicKeyToken=407dd0808d44fbdc, processorArchitecture=MSIL">
+      <HintPath>packages\Castle.Core.5.1.1\lib\net462\Castle.Core.dll</HintPath>
+    </Reference>
+    <Reference Include="Microsoft.VisualStudio.CodeCoverage.Shim, Version=15.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>packages\Microsoft.CodeCoverage.17.7.1\lib\net462\Microsoft.VisualStudio.CodeCoverage.Shim.dll</HintPath>
+    </Reference>
+    <Reference Include="Moq, Version=4.20.69.0, Culture=neutral, PublicKeyToken=69f491c39445e920, processorArchitecture=MSIL">
+      <HintPath>packages\Moq.4.20.69\lib\net462\Moq.dll</HintPath>
+    </Reference>
     <Reference Include="System" />
+    <Reference Include="System.Configuration" />
+    <Reference Include="System.Runtime.CompilerServices.Unsafe, Version=4.0.4.1, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>packages\System.Runtime.CompilerServices.Unsafe.4.5.3\lib\net461\System.Runtime.CompilerServices.Unsafe.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Threading.Tasks.Extensions, Version=4.2.0.1, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>packages\System.Threading.Tasks.Extensions.4.5.4\lib\net461\System.Threading.Tasks.Extensions.dll</HintPath>
+    </Reference>
     <Reference Include="System.Web" />
     <Reference Include="nunit.framework">
       <HintPath>lib\nunit.framework.dll</HintPath>
@@ -45,9 +67,14 @@
     <Compile Include="TelemetrySystem\TelemetryClient.cs" />
     <Compile Include="TelemetrySystem.Tests\TelemetryDiagnosticControlsTest.cs" />
     <Compile Include="TelemetrySystem\TelemetryDiagnosticControls.cs" />
+    <Compile Include="TirePressureMonitoringSystem.Test\AlarmTest.cs" />
     <Compile Include="TirePressureMonitoringSystem\Alarm.cs" />
+    <Compile Include="TirePressureMonitoringSystem\ISensor.cs" />
     <Compile Include="TirePressureMonitoringSystem\Sensor.cs" />
+    <Compile Include="TurnTicketDispenser.Test\TicketDispenserTest.cs" />
+    <Compile Include="TurnTicketDispenser\ITurnNumberSequence.cs" />
     <Compile Include="TurnTicketDispenser\TicketDispenser.cs" />
+    <Compile Include="TurnTicketDispenser\TicketDispenserFactory.cs" />
     <Compile Include="TurnTicketDispenser\TurnNumberSequence.cs" />
     <Compile Include="TurnTicketDispenser\TurnTicket.cs" />
     <Compile Include="UnicodeFileToHtmlTextConverter\UnicodeFileToHtmlTextConverter.cs" />
@@ -67,17 +94,25 @@
     <Compile Include="TelemetrySystem.SomeDependencies\TelemetryDiagnosticControlsClient2.cs" />
     <Compile Include="TelemetrySystem.SomeDependencies\TelemetryDiagnosticControlsClient3.cs" />
   </ItemGroup>
-  <ItemGroup>
-    <Folder Include="TirePressureMonitoringSystem.SomeDependencies\" />
-    <Folder Include="UnicodeFileToHtmlTextConverter.SomeDependencies\" />
-    <Folder Include="TurnTicketDispenser.SomeDependencies\" />
-    <Folder Include="TelemetrySystem.SomeDependencies\" />
-  </ItemGroup>
+  <ItemGroup />
   <ItemGroup>
     <None Include="lib\nunit.framework.dll" />
     <None Include="lib\nunit.framework.xml" />
+    <None Include="packages.config" />
   </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
+  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
+    <PropertyGroup>
+      <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
+    </PropertyGroup>
+    <Error Condition="!Exists('packages\NUnit3TestAdapter.3.17.0\build\net35\NUnit3TestAdapter.props')" Text="$([System.String]::Format('$(ErrorText)', 'packages\NUnit3TestAdapter.3.17.0\build\net35\NUnit3TestAdapter.props'))" />
+    <Error Condition="!Exists('packages\Microsoft.CodeCoverage.17.7.1\build\netstandard2.0\Microsoft.CodeCoverage.props')" Text="$([System.String]::Format('$(ErrorText)', 'packages\Microsoft.CodeCoverage.17.7.1\build\netstandard2.0\Microsoft.CodeCoverage.props'))" />
+    <Error Condition="!Exists('packages\Microsoft.CodeCoverage.17.7.1\build\netstandard2.0\Microsoft.CodeCoverage.targets')" Text="$([System.String]::Format('$(ErrorText)', 'packages\Microsoft.CodeCoverage.17.7.1\build\netstandard2.0\Microsoft.CodeCoverage.targets'))" />
+    <Error Condition="!Exists('packages\Microsoft.NET.Test.Sdk.17.7.1\build\net462\Microsoft.NET.Test.Sdk.props')" Text="$([System.String]::Format('$(ErrorText)', 'packages\Microsoft.NET.Test.Sdk.17.7.1\build\net462\Microsoft.NET.Test.Sdk.props'))" />
+    <Error Condition="!Exists('packages\Microsoft.NET.Test.Sdk.17.7.1\build\net462\Microsoft.NET.Test.Sdk.targets')" Text="$([System.String]::Format('$(ErrorText)', 'packages\Microsoft.NET.Test.Sdk.17.7.1\build\net462\Microsoft.NET.Test.Sdk.targets'))" />
+  </Target>
+  <Import Project="packages\Microsoft.CodeCoverage.17.7.1\build\netstandard2.0\Microsoft.CodeCoverage.targets" Condition="Exists('packages\Microsoft.CodeCoverage.17.7.1\build\netstandard2.0\Microsoft.CodeCoverage.targets')" />
+  <Import Project="packages\Microsoft.NET.Test.Sdk.17.7.1\build\net462\Microsoft.NET.Test.Sdk.targets" Condition="Exists('packages\Microsoft.NET.Test.Sdk.17.7.1\build\net462\Microsoft.NET.Test.Sdk.targets')" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">
diff --git a/src/TDDMicroExercises.sln b/src/TDDMicroExercises.sln
index 7255acd..0a78216 100644
--- a/src/TDDMicroExercises.sln
+++ b/src/TDDMicroExercises.sln
@@ -1,8 +1,12 @@
 
-Microsoft Visual Studio Solution File, Format Version 11.00
-# Visual Studio 2010
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.7.34018.315
+MinimumVisualStudioVersion = 10.0.40219.1
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "TDDMicroExercises", "TDDMicroExercises.csproj", "{BBCF3C67-8E31-48E3-AD2E-8C605E2E07BE}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "UnitTesting", "..\UnitTesting\UnitTesting.csproj", "{FB81D6CC-2878-438A-B0EA-437569070FF9}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -13,8 +17,15 @@ Global
 		{BBCF3C67-8E31-48E3-AD2E-8C605E2E07BE}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{BBCF3C67-8E31-48E3-AD2E-8C605E2E07BE}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{BBCF3C67-8E31-48E3-AD2E-8C605E2E07BE}.Release|Any CPU.Build.0 = Release|Any CPU
+		{FB81D6CC-2878-438A-B0EA-437569070FF9}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{FB81D6CC-2878-438A-B0EA-437569070FF9}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{FB81D6CC-2878-438A-B0EA-437569070FF9}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{FB81D6CC-2878-438A-B0EA-437569070FF9}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
 	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {3CE70FFC-7088-41BE-9345-6F47335DF3C3}
+	EndGlobalSection
 EndGlobal
diff --git a/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient1.cs b/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient1.cs
index 95cd3ff..da25ce5 100644
--- a/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient1.cs
+++ b/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient1.cs
@@ -6,9 +6,8 @@ public class AnAlarmClient1
 		// A class with the only goal of simulating a dependency on Alert
 		// that has impact on the refactoring.
 		
-        public AnAlarmClient1()
+        public AnAlarmClient1(Alarm anAlarm)
         {
-            Alarm anAlarm = new Alarm();
             anAlarm.Check();
             bool isAlarmOn = anAlarm.AlarmOn;
         }
diff --git a/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient2.cs b/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient2.cs
index 615d021..bedbd22 100644
--- a/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient2.cs
+++ b/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient2.cs
@@ -3,14 +3,17 @@ namespace TDDMicroExercises.TirePressureMonitoringSystem.SomeDependencies
 {
     public class AnAlarmClient2
     {
-		// A class with the only goal of simulating a dependency on Alert
-		// that has impact on the refactoring.
-		
-        private void DoSomething()
+        private readonly Alarm _anAlarm;
+        // A class with the only goal of simulating a dependency on Alert
+        // that has impact on the refactoring.
+        public AnAlarmClient2(Alarm anAlarm)
         {
-            Alarm anAlarm = new Alarm();
-            anAlarm.Check();
-            bool isAlarmOn = anAlarm.AlarmOn;
+            _anAlarm = anAlarm;
+        }
+        private void DoSomething()
+        {           
+            _anAlarm.Check();
+            bool isAlarmOn = _anAlarm.AlarmOn;
         }
     }
 }
diff --git a/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient3.cs b/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient3.cs
index 32fe3b7..d664c4c 100644
--- a/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient3.cs
+++ b/src/TirePressureMonitoringSystem.SomeDependencies/AnAlarmClient3.cs
@@ -8,9 +8,9 @@ public class AnAlarmClient3
 
         private Alarm _anAlarm;
 
-        public AnAlarmClient3()
+        public AnAlarmClient3(Alarm anAlarm)
         {
-            _anAlarm = new Alarm();
+            _anAlarm = anAlarm;
         }
 
         public void DoSomething() 
diff --git a/src/TirePressureMonitoringSystem.Test/AlarmTest.cs b/src/TirePressureMonitoringSystem.Test/AlarmTest.cs
new file mode 100644
index 0000000..abc8904
--- /dev/null
+++ b/src/TirePressureMonitoringSystem.Test/AlarmTest.cs
@@ -0,0 +1,46 @@
+using Moq;
+using NUnit.Framework;
+
+namespace TDDMicroExercises.TirePressureMonitoringSystem.Test
+{
+    //Testing the Alarm class using mock implementation of Sensor
+    [TestFixture]
+    public class AlarmTest
+    {
+        [Test]
+        public void Check_WhetherAlarmOnWhenPressureBelowLowThreshold()
+        {
+            var mockSensor = new Mock<ISensor>();
+            mockSensor.Setup(sensor => sensor.PopNextPressurePsiValue()).Returns(15); 
+            var alarm = new Alarm(mockSensor.Object);
+
+            alarm.Check();
+
+            Assert.IsTrue(alarm.AlarmOn);
+        }
+
+        [Test]
+        public void Check_WhetherAlarmOnWhenPressureAboveHighThreshold()
+        {
+            var mockSensor = new Mock<ISensor>();
+            mockSensor.Setup(sensor => sensor.PopNextPressurePsiValue()).Returns(22); 
+            var alarm = new Alarm(mockSensor.Object);
+
+            alarm.Check();
+
+            Assert.IsTrue(alarm.AlarmOn);
+        }
+
+        [Test]
+        public void Check_WhetherAlarmOffWhenPressureWithinThresholdRange()
+        {
+            var mockSensor = new Mock<ISensor>();
+            mockSensor.Setup(sensor => sensor.PopNextPressurePsiValue()).Returns(18);
+            var alarm = new Alarm(mockSensor.Object);
+
+            alarm.Check();
+
+            Assert.IsFalse(alarm.AlarmOn);
+        }
+    }
+}
diff --git a/src/TirePressureMonitoringSystem/Alarm.cs b/src/TirePressureMonitoringSystem/Alarm.cs
index 9aba52d..0de6096 100644
--- a/src/TirePressureMonitoringSystem/Alarm.cs
+++ b/src/TirePressureMonitoringSystem/Alarm.cs
@@ -1,14 +1,22 @@
 namespace TDDMicroExercises.TirePressureMonitoringSystem
 {
+    /* Dependency Inversion Principle Violation:
+    It was directly dependent on  sensor
+    which made it hard to mock the sensor during testing.*/
     public class Alarm
     {
         private const double LowPressureThreshold = 17;
         private const double HighPressureThreshold = 21;
 
-        readonly Sensor _sensor = new Sensor();
+        private readonly ISensor _sensor;
 
         bool _alarmOn = false;
 
+        public Alarm(ISensor sensor)
+        {
+            _sensor = sensor;
+        }
+
         public void Check()
         {
             double psiPressureValue = _sensor.PopNextPressurePsiValue();
diff --git a/src/TirePressureMonitoringSystem/ISensor.cs b/src/TirePressureMonitoringSystem/ISensor.cs
new file mode 100644
index 0000000..2e54552
--- /dev/null
+++ b/src/TirePressureMonitoringSystem/ISensor.cs
@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace TDDMicroExercises.TirePressureMonitoringSystem
+{
+    public interface ISensor
+    {
+        double PopNextPressurePsiValue();
+    }
+}
diff --git a/src/TirePressureMonitoringSystem/Sensor.cs b/src/TirePressureMonitoringSystem/Sensor.cs
index d48ce79..9754bfb 100644
--- a/src/TirePressureMonitoringSystem/Sensor.cs
+++ b/src/TirePressureMonitoringSystem/Sensor.cs
@@ -2,7 +2,7 @@
 
 namespace TDDMicroExercises.TirePressureMonitoringSystem
 {
-    public class Sensor
+    public class Sensor:ISensor
     {
         //
         // The reading of the pressure value from the sensor is simulated in this implementation.
diff --git a/src/TurnTicketDispenser.SomeDependencies/TicketDispenserClient.cs b/src/TurnTicketDispenser.SomeDependencies/TicketDispenserClient.cs
index c7623a8..9aa57af 100644
--- a/src/TurnTicketDispenser.SomeDependencies/TicketDispenserClient.cs
+++ b/src/TurnTicketDispenser.SomeDependencies/TicketDispenserClient.cs
@@ -3,14 +3,19 @@ namespace TDDMicroExercises.TurnTicketDispenser.SomeDependencies
 {
     public class TicketDispenserClient
     {
-		// A class with the only goal of simulating a dependency on TicketDispenser
-		// that has impact on the refactoring.
+        // A class with the only goal of simulating a dependency on TicketDispenser
+        // that has impact on the refactoring.
+        private readonly TicketDispenser _ticketDispenser;
 
-		public TicketDispenserClient()
+        public TicketDispenserClient(TicketDispenser ticketDispenser)
         {
-			new TicketDispenser().GetTurnTicket();
-			new TicketDispenser().GetTurnTicket();
-			new TicketDispenser().GetTurnTicket();
+            _ticketDispenser = ticketDispenser;
+        }
+        public TicketDispenserClient()
+        {
+            _ticketDispenser.GetTurnTicket();
+            _ticketDispenser.GetTurnTicket();
+            _ticketDispenser.GetTurnTicket();
 		}
     }
 }
diff --git a/src/TurnTicketDispenser.SomeDependencies/TurnNumberSequenceClient.cs b/src/TurnTicketDispenser.SomeDependencies/TurnNumberSequenceClient.cs
index 8c896f8..410f31f 100644
--- a/src/TurnTicketDispenser.SomeDependencies/TurnNumberSequenceClient.cs
+++ b/src/TurnTicketDispenser.SomeDependencies/TurnNumberSequenceClient.cs
@@ -3,15 +3,22 @@ namespace TDDMicroExercises.TurnTicketDispenser.SomeDependencies
 {
     public class TurnNumberSequenceClient
     {
-		// A class with the only goal of simulating a dependency on TurnNumberSequence
-		// that has impact on the refactoring.
+        private readonly ITurnNumberSequence _turnNumberSequence;
 
-		public TurnNumberSequenceClient()
+        public TurnNumberSequenceClient(ITurnNumberSequence turnNumberSequence)
+        {
+            _turnNumberSequence = turnNumberSequence;
+        }
+
+        // A class with the only goal of simulating a dependency on TurnNumberSequence
+        // that has impact on the refactoring.
+
+        public TurnNumberSequenceClient()
         {
             int nextUniqueTicketNumber;
-            nextUniqueTicketNumber = TurnNumberSequence.GetNextTurnNumber();
-			nextUniqueTicketNumber = TurnNumberSequence.GetNextTurnNumber();
-			nextUniqueTicketNumber = TurnNumberSequence.GetNextTurnNumber();
-		}
+            nextUniqueTicketNumber = _turnNumberSequence.GetNextTurnNumber();
+            nextUniqueTicketNumber = _turnNumberSequence.GetNextTurnNumber();
+            nextUniqueTicketNumber = _turnNumberSequence.GetNextTurnNumber();
+        }
     }
 }
diff --git a/src/TurnTicketDispenser.SomeDependencies/TurnTicketAndSequenceClient.cs b/src/TurnTicketDispenser.SomeDependencies/TurnTicketAndSequenceClient.cs
index 0ea0ff9..2337efd 100644
--- a/src/TurnTicketDispenser.SomeDependencies/TurnTicketAndSequenceClient.cs
+++ b/src/TurnTicketDispenser.SomeDependencies/TurnTicketAndSequenceClient.cs
@@ -3,14 +3,19 @@ namespace TDDMicroExercises.TurnTicketDispenser.SomeDependencies
 {
     public class TurnTicketAndSequenceClient
     {
-		// A class with the only goal of simulating a dependencies on 
-		// TurnNumberSequence and TurnTicket that have impact on the refactoring.
+        // A class with the only goal of simulating a dependencies on 
+        // TurnNumberSequence and TurnTicket that have impact on the refactoring.
+        private readonly ITurnNumberSequence _turnNumberSequence;
 
-		public TurnTicketAndSequenceClient()
+        public TurnTicketAndSequenceClient(ITurnNumberSequence turnNumberSequence)
         {
-			var turnTicket1 = new TurnTicket(TurnNumberSequence.GetNextTurnNumber());
-			var turnTicket2 = new TurnTicket(TurnNumberSequence.GetNextTurnNumber());
-			var turnTicket3 = new TurnTicket(TurnNumberSequence.GetNextTurnNumber());
+            _turnNumberSequence = turnNumberSequence;
         }
+        public TurnTicketAndSequenceClient()
+        {
+			var turnTicket1 = new TurnTicket(_turnNumberSequence.GetNextTurnNumber());
+			var turnTicket2 = new TurnTicket(_turnNumberSequence.GetNextTurnNumber());
+			var turnTicket3 = new TurnTicket(_turnNumberSequence.GetNextTurnNumber());
+		}
     }
 }
diff --git a/src/TurnTicketDispenser.Test/TicketDispenserTest.cs b/src/TurnTicketDispenser.Test/TicketDispenserTest.cs
new file mode 100644
index 0000000..9808406
--- /dev/null
+++ b/src/TurnTicketDispenser.Test/TicketDispenserTest.cs
@@ -0,0 +1,77 @@
+using Moq;
+using NUnit.Framework;
+
+namespace TDDMicroExercises.TurnTicketDispenser.Test
+{
+    //Testing the TicketDispenser class using mock implementation of ITurnNumberSource
+
+    [TestFixture]
+    public class TicketDispenserTest
+    {
+        [Test]
+        public void Dispenser_ShouldReturnNonNegativeTicketTurnNumber()
+        {
+            var mockTurnNumberSequence = new Mock<ITurnNumberSequence>();
+            mockTurnNumberSequence.Setup(seq => seq.GetNextTurnNumber()).Returns(1);
+
+            var dispenser = new TicketDispenser(mockTurnNumberSequence.Object);
+            var ticket = dispenser.GetTurnTicket();
+
+            Assert.That(ticket.TurnNumber, Is.GreaterThanOrEqualTo(0));
+        }
+
+        [Test]
+        public void Dispenser_ShouldReturnSubsequentTicketTurnNumberEveryTime()
+        {
+            var mockTurnNumberSequence = new Mock<ITurnNumberSequence>();
+            mockTurnNumberSequence.SetupSequence(seq => seq.GetNextTurnNumber())
+                .Returns(1)
+                .Returns(2)
+                .Returns(3);
+
+            var ticketDispenser = new TicketDispenser(mockTurnNumberSequence.Object);
+
+            var ticket1 = ticketDispenser.GetTurnTicket();
+            var ticket2 = ticketDispenser.GetTurnTicket();
+            var ticket3 = ticketDispenser.GetTurnTicket();
+
+            Assert.AreEqual(1, ticket1.TurnNumber);
+            Assert.AreEqual(2, ticket2.TurnNumber);
+            Assert.AreEqual(3, ticket3.TurnNumber);
+        }
+
+        [Test]
+        public void MultipleDispensers_ShouldReturnSubsequentTicketTurnNumber()
+        {
+            var mockTurnNumberSequence = new Mock<ITurnNumberSequence>();
+            mockTurnNumberSequence.SetupSequence(seq => seq.GetNextTurnNumber())
+                .Returns(11)
+                .Returns(12);
+
+            var dispenser1 = new TicketDispenser(mockTurnNumberSequence.Object);
+            var dispenser2 = new TicketDispenser(mockTurnNumberSequence.Object);
+
+            var ticket1 = dispenser1.GetTurnTicket();
+            var ticket2 = dispenser2.GetTurnTicket();
+
+            Assert.AreEqual(11, ticket1.TurnNumber);
+            Assert.AreEqual(12, ticket2.TurnNumber);
+        }
+
+        [Test]
+        public void MultipleDispensers_ShouldReturnDistinctTicketTurnNumber()
+        {
+            var turnNumberSequence = new TurnNumberSequence();
+            var dispenserFactory = new TicketDispenserFactory(turnNumberSequence);
+
+            var dispenser1 = dispenserFactory.CreateTicketDispenser();
+            var dispenser2 = dispenserFactory.CreateTicketDispenser();
+
+            var ticket1 = dispenser1.GetTurnTicket();
+            var ticket2 = dispenser2.GetTurnTicket();
+
+            Assert.That(ticket1.TurnNumber, Is.Not.EqualTo(ticket2.TurnNumber));
+        }
+
+    }
+}
diff --git a/src/TurnTicketDispenser/ITurnNumberSequence.cs b/src/TurnTicketDispenser/ITurnNumberSequence.cs
new file mode 100644
index 0000000..07d3b28
--- /dev/null
+++ b/src/TurnTicketDispenser/ITurnNumberSequence.cs
@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace TDDMicroExercises.TurnTicketDispenser
+{
+    public interface ITurnNumberSequence
+    {
+        int GetNextTurnNumber();
+    }
+    
+}
diff --git a/src/TurnTicketDispenser/TicketDispenser.cs b/src/TurnTicketDispenser/TicketDispenser.cs
index d0855f2..88ed443 100644
--- a/src/TurnTicketDispenser/TicketDispenser.cs
+++ b/src/TurnTicketDispenser/TicketDispenser.cs
@@ -1,10 +1,23 @@
+using Moq;
+using System;
+
 namespace TDDMicroExercises.TurnTicketDispenser
 {
+    /* Dependency Inversion Principle Violation:
+    It was directly dependent on the static methods of TurnNumberSequence
+    which made it hard to mock the TurnNumberSequence during testing.*/
     public class TicketDispenser
     {
+        private readonly ITurnNumberSequence _turnNumberSequence;
+
+        public TicketDispenser(ITurnNumberSequence turnNumberSequence)
+        {
+            _turnNumberSequence = turnNumberSequence;
+        }
+
         public TurnTicket GetTurnTicket()
         {
-            int newTurnNumber = TurnNumberSequence.GetNextTurnNumber();
+            int newTurnNumber = _turnNumberSequence.GetNextTurnNumber();
             var newTurnTicket = new TurnTicket(newTurnNumber);
 
             return newTurnTicket;
diff --git a/src/TurnTicketDispenser/TicketDispenserFactory.cs b/src/TurnTicketDispenser/TicketDispenserFactory.cs
new file mode 100644
index 0000000..9af82f0
--- /dev/null
+++ b/src/TurnTicketDispenser/TicketDispenserFactory.cs
@@ -0,0 +1,23 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace TDDMicroExercises.TurnTicketDispenser
+{
+    public class TicketDispenserFactory
+    {
+        private readonly ITurnNumberSequence _turnNumberSequence;
+
+        public TicketDispenserFactory(ITurnNumberSequence turnNumberSequence)
+        {
+            _turnNumberSequence = turnNumberSequence;
+        }
+
+        public TicketDispenser CreateTicketDispenser()
+        {
+            return new TicketDispenser(_turnNumberSequence);
+        }
+    }
+}
diff --git a/src/TurnTicketDispenser/TurnNumberSequence.cs b/src/TurnTicketDispenser/TurnNumberSequence.cs
index 543111f..c90705a 100644
--- a/src/TurnTicketDispenser/TurnNumberSequence.cs
+++ b/src/TurnTicketDispenser/TurnNumberSequence.cs
@@ -1,10 +1,10 @@
 namespace TDDMicroExercises.TurnTicketDispenser
 {
-    public static class TurnNumberSequence
+    public class TurnNumberSequence : ITurnNumberSequence
     {
         private static int _turnNumber = 0;
 
-        public static int GetNextTurnNumber()
+        public int GetNextTurnNumber()
         {
             return _turnNumber++;
         }
diff --git a/src/packages.config b/src/packages.config
new file mode 100644
index 0000000..47849be
--- /dev/null
+++ b/src/packages.config
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="Castle.Core" version="5.1.1" targetFramework="net48" />
+  <package id="Microsoft.CodeCoverage" version="17.7.1" targetFramework="net48" />
+  <package id="Microsoft.NET.Test.Sdk" version="17.7.1" targetFramework="net48" />
+  <package id="Moq" version="4.20.69" targetFramework="net48" />
+  <package id="NUnit3TestAdapter" version="3.17.0" targetFramework="net48" />
+  <package id="System.Runtime.CompilerServices.Unsafe" version="4.5.3" targetFramework="net48" />
+  <package id="System.Threading.Tasks.Extensions" version="4.5.4" targetFramework="net48" />
+</packages>
\ No newline at end of file