diff --git a/src/Fluxera.Extensions.Validation.Abstractions/Fluxera.Extensions.Validation.Abstractions.csproj b/src/Fluxera.Extensions.Validation.Abstractions/Fluxera.Extensions.Validation.Abstractions.csproj
index 1929a58..133fa31 100644
--- a/src/Fluxera.Extensions.Validation.Abstractions/Fluxera.Extensions.Validation.Abstractions.csproj
+++ b/src/Fluxera.Extensions.Validation.Abstractions/Fluxera.Extensions.Validation.Abstractions.csproj
@@ -28,6 +28,7 @@
 	<ItemGroup>
 		<PackageReference Include="Fluxera.Guards" Version="6.0.5" />
 		<PackageReference Include="JetBrains.Annotations" Version="2021.3.0" />
+		<PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="6.0.0" />
 	</ItemGroup>
 
 </Project>
\ No newline at end of file
diff --git a/src/Fluxera.Extensions.Validation.Abstractions/IValidationBuilder.cs b/src/Fluxera.Extensions.Validation.Abstractions/IValidationBuilder.cs
new file mode 100644
index 0000000..6faecb0
--- /dev/null
+++ b/src/Fluxera.Extensions.Validation.Abstractions/IValidationBuilder.cs
@@ -0,0 +1,15 @@
+namespace Fluxera.Extensions.Validation
+{
+	using JetBrains.Annotations;
+	using Microsoft.Extensions.DependencyInjection;
+
+	[PublicAPI]
+	public interface IValidationBuilder
+	{
+		IValidationBuilder AddValidatorFactory<T>() where T : class, IValidatorFactory;
+
+		IValidationBuilder AddValidatorFactoryNamed<T>(string name) where T : class, IValidatorFactory;
+
+		IServiceCollection Services { get; }
+	}
+}
diff --git a/src/Fluxera.Extensions.Validation.Abstractions/IValidator.cs b/src/Fluxera.Extensions.Validation.Abstractions/IValidator.cs
new file mode 100644
index 0000000..773223e
--- /dev/null
+++ b/src/Fluxera.Extensions.Validation.Abstractions/IValidator.cs
@@ -0,0 +1,14 @@
+namespace Fluxera.Extensions.Validation
+{
+	using System.Threading.Tasks;
+	using JetBrains.Annotations;
+
+	/// <summary>
+	///		A contract for validators. The underlying validation frameworks must implement this.
+	/// </summary>
+	[PublicAPI]
+	public interface IValidator
+	{
+		Task<ValidationResult> ValidateAsync(object instance);
+	}
+}
diff --git a/src/Fluxera.Extensions.Validation/IValidatorFactory.cs b/src/Fluxera.Extensions.Validation.Abstractions/IValidatorFactory.cs
similarity index 100%
rename from src/Fluxera.Extensions.Validation/IValidatorFactory.cs
rename to src/Fluxera.Extensions.Validation.Abstractions/IValidatorFactory.cs
diff --git a/src/Fluxera.Extensions.Validation.DataAnnotations/ValidationBuilderExtensions.cs b/src/Fluxera.Extensions.Validation.DataAnnotations/ValidationBuilderExtensions.cs
index daf52cf..b227788 100644
--- a/src/Fluxera.Extensions.Validation.DataAnnotations/ValidationBuilderExtensions.cs
+++ b/src/Fluxera.Extensions.Validation.DataAnnotations/ValidationBuilderExtensions.cs
@@ -10,7 +10,7 @@ public static class ValidationBuilderExtensions
 		/// </summary>
 		/// <param name="builder">The builder.</param>
 		/// <returns>The builder.</returns>
-		public static ValidationBuilder AddDataAnnotations(this ValidationBuilder builder)
+		public static IValidationBuilder AddDataAnnotations(this IValidationBuilder builder)
 		{
 			builder.AddValidatorFactory<DataAnnotationsValidationValidatorFactory>();
 
@@ -23,7 +23,7 @@ public static ValidationBuilder AddDataAnnotations(this ValidationBuilder builde
 		///  <param name="builder">The builder.</param>
 		///  <param name="name">The name of the validator factory.</param>
 		///  <returns>The builder.</returns>
-		public static ValidationBuilder AddDataAnnotations(this ValidationBuilder builder, string name)
+		public static IValidationBuilder AddDataAnnotations(this IValidationBuilder builder, string name)
 		{
 			builder.AddValidatorFactoryNamed<DataAnnotationsValidationValidatorFactory>(name);
 
diff --git a/src/Fluxera.Extensions.Validation.FluentValidation/ValidationBuilderExtensions.cs b/src/Fluxera.Extensions.Validation.FluentValidation/ValidationBuilderExtensions.cs
index 8e50ec1..304b855 100644
--- a/src/Fluxera.Extensions.Validation.FluentValidation/ValidationBuilderExtensions.cs
+++ b/src/Fluxera.Extensions.Validation.FluentValidation/ValidationBuilderExtensions.cs
@@ -13,7 +13,7 @@ public static class ValidationBuilderExtensions
 		///  <param name="builder">The builder.</param>
 		///  <param name="configure">Action to configure the registered validators.</param>
 		///  <returns>The builder.</returns>
-		public static ValidationBuilder AddFluentValidation(this ValidationBuilder builder, Action<ValidatorRegistration> configure)
+		public static IValidationBuilder AddFluentValidation(this IValidationBuilder builder, Action<ValidatorRegistration> configure)
 		{
 			Guard.Against.Null(builder, nameof(builder));
 			Guard.Against.Null(configure, nameof(configure));
@@ -32,7 +32,7 @@ public static ValidationBuilder AddFluentValidation(this ValidationBuilder build
 		///  <param name="name">The name of the validator factory.</param>
 		///  <param name="configure">Action to configure the registered validators.</param>
 		///  <returns>The builder.</returns>
-		public static ValidationBuilder AddFluentValidation(this ValidationBuilder builder, string name, Action<ValidatorRegistration> configure)
+		public static IValidationBuilder AddFluentValidation(this IValidationBuilder builder, string name, Action<ValidatorRegistration> configure)
 		{
 			Guard.Against.Null(builder, nameof(builder));
 			Guard.Against.Null(configure, nameof(configure));
diff --git a/src/Fluxera.Extensions.Validation/IValidator.cs b/src/Fluxera.Extensions.Validation/IValidator.cs
deleted file mode 100644
index d90fa10..0000000
--- a/src/Fluxera.Extensions.Validation/IValidator.cs
+++ /dev/null
@@ -1,3 +0,0 @@
-namespace Fluxera.Extensions.Validation
{
	using System.Threading.Tasks;
	using JetBrains.Annotations;

	/// <summary>
-	///		A contract for validators. The underlying validation frameworks must implement this.
-	/// </summary>
	[PublicAPI]
	public interface IValidator
	{
		Task<ValidationResult> ValidateAsync(object instance);
	}
}
\ No newline at end of file
diff --git a/src/Fluxera.Extensions.Validation/ServiceCollectionExtensions.cs b/src/Fluxera.Extensions.Validation/ServiceCollectionExtensions.cs
index 83a7c18..804c889 100644
--- a/src/Fluxera.Extensions.Validation/ServiceCollectionExtensions.cs
+++ b/src/Fluxera.Extensions.Validation/ServiceCollectionExtensions.cs
@@ -15,7 +15,7 @@ public static class ServiceCollectionExtensions
 		/// <param name="services">The service collection.</param>
 		/// <param name="configure">The action that configure the underlying validation framework.</param>
 		/// <returns>The service collection.</returns>
-		public static IServiceCollection AddValidation(this IServiceCollection services, Action<ValidationBuilder>? configure)
+		public static IServiceCollection AddValidation(this IServiceCollection services, Action<IValidationBuilder> configure)
 		{
 			Guard.Against.Null(services, nameof(services));
 
@@ -27,5 +27,20 @@ public static IServiceCollection AddValidation(this IServiceCollection services,
 
 			return services;
 		}
+
+		/// <summary>
+		///		Adds the validation service and configures the underlying validation framework.
+		/// </summary>
+		/// <param name="services">The service collection.</param>
+		/// <returns>The service collection.</returns>
+		public static IServiceCollection AddValidation(this IServiceCollection services)
+		{
+			Guard.Against.Null(services, nameof(services));
+
+			// Register validation service.
+			services.TryAddTransient<IValidationService, ValidationService>();
+
+			return services;
+		}
 	}
 }
diff --git a/src/Fluxera.Extensions.Validation/ValidationBuilder.cs b/src/Fluxera.Extensions.Validation/ValidationBuilder.cs
index e51ee22..a05a613 100644
--- a/src/Fluxera.Extensions.Validation/ValidationBuilder.cs
+++ b/src/Fluxera.Extensions.Validation/ValidationBuilder.cs
@@ -7,7 +7,7 @@
 	using Microsoft.Extensions.DependencyInjection.Extensions;
 
 	[PublicAPI]
-	public sealed class ValidationBuilder
+	internal sealed class ValidationBuilder : IValidationBuilder
 	{
 		public ValidationBuilder(IServiceCollection services)
 		{
@@ -16,9 +16,7 @@ public ValidationBuilder(IServiceCollection services)
 			this.Services = services;
 		}
 
-		public IServiceCollection Services { get; }
-
-		public ValidationBuilder AddValidatorFactory<T>() where T : class, IValidatorFactory
+		public IValidationBuilder AddValidatorFactory<T>() where T : class, IValidatorFactory
 		{
 			this.Services.TryAddTransient<T>();
 			this.Services.AddTransient<IValidatorFactory, T>();
@@ -26,7 +24,7 @@ public ValidationBuilder AddValidatorFactory<T>() where T : class, IValidatorFac
 			return this;
 		}
 
-		public ValidationBuilder AddValidatorFactoryNamed<T>(string name) where T : class, IValidatorFactory
+		public IValidationBuilder AddValidatorFactoryNamed<T>(string name) where T : class, IValidatorFactory
 		{
 			this.Services.AddNamedTransient<IValidatorFactory>(builder =>
 			{
@@ -35,5 +33,8 @@ public ValidationBuilder AddValidatorFactoryNamed<T>(string name) where T : clas
 
 			return this;
 		}
+
+		/// <inheritdoc />
+		public IServiceCollection Services { get; }
 	}
 }