diff --git a/Controllers/Applications/ApplicationsController+Custom.cs b/Controllers/Applications/ApplicationsController+Custom.cs
index ddbe141..fa9ae51 100644
--- a/Controllers/Applications/ApplicationsController+Custom.cs
+++ b/Controllers/Applications/ApplicationsController+Custom.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using xIdentityHelper;
 using System.Threading;
 using xCommons.Attributes;
@@ -17,6 +18,13 @@ namespace xIds.Controllers
 {
     public partial class ApplicationsController
     {
+        /// <summary>
+        /// Create Api Key ...
+        /// </summary>
+        /// <param name="applicationId"></param>
+        /// <param name="request"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
         [RequireXPowered]
         [Authorize(LocalApi.PolicyName)]
         [Authorize(Policy = XPolicies.EnabledUser)]
@@ -56,7 +64,6 @@ namespace xIds.Controllers
                 }
 
                 //
-                // Create Specified Api Key ...
                 var result = await provider.CreateApiKey(
                     userInfo: userInfo,
                     scopes: request.Scopes,
@@ -78,6 +85,13 @@ namespace xIds.Controllers
             }
         }
 
+        /// <summary>
+        /// Remove Specified Api Key ...
+        /// </summary>
+        /// <param name="apiKeyId"></param>
+        /// <param name="applicationId"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
         [RequireXPowered]
         [Authorize(LocalApi.PolicyName)]
         [Authorize(Policy = XPolicies.EnabledUser)]
@@ -117,7 +131,6 @@ namespace xIds.Controllers
                 }
 
                 //
-                // Create Specified Api Key ...
                 var result = await provider.RemoveApiKeyAsync(
                     id: apiKeyId,
                     softDelete: false,
@@ -136,6 +149,14 @@ namespace xIds.Controllers
             }
         }
 
+        /// <summary>
+        /// Rotate Specified Api Key ...
+        /// </summary>
+        /// <param name="apiKeyId"></param>
+        /// <param name="applicationId"></param>
+        /// <param name="request"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
         [RequireXPowered]
         [Authorize(LocalApi.PolicyName)]
         [Authorize(Policy = XPolicies.EnabledUser)]
@@ -192,7 +213,6 @@ namespace xIds.Controllers
                 }
 
                 //
-                // Create Specified Api Key ...
                 var result = await provider.RotateApiKey(
                     apiKeyId: apiKeyId,
                     userInfo: userInfo,
@@ -211,19 +231,75 @@ namespace xIds.Controllers
             }
         }
 
+        /// <summary>
+        /// Revoke Specified Api Key ...
+        /// </summary>
+        /// <param name="apiKeyId"></param>
+        /// <param name="applicationId"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
         [RequireXPowered]
         [Authorize(LocalApi.PolicyName)]
         [Authorize(Policy = XPolicies.EnabledUser)]
         [HttpPost("Applications/{applicationId}/ApiKeys/{apiKeyId}/Revoke")]
-        public async Task<ActionResult<XApiKeyDto>> RevokeApiKey(
+        public async Task<ActionResult<bool>> RevokeApiKey(
             [FromRoute] Guid apiKeyId,
             [FromRoute] int applicationId,
             CancellationToken cancellationToken = default
         )
         {
-            throw new NotImplementedException();            
+            //
+            try
+            {
+                //
+                // Validate ...
+                if (
+                    apiKeyId.IsDefaultGuid() ||
+                    !applicationId.IsValidIntId())
+                {
+                    XException.InvalidArgs.Throw();
+                }
+
+                //
+                var userInfo = await GetUserInfo();
+
+                //
+                // Retrieve Application for Validating ...
+                var application = await provider.GetApplicationAsync(
+                    id: applicationId,
+                    userInfo: userInfo,
+                    includeBuilder: null,
+                    ignoreSoftDeleteds: true
+                );
+                if (application.IsNullOrDefault())
+                {
+                    XException.NotFound.Throw();
+                }
+
+                //
+                var result = await provider.RevokeApiKey(
+                    apiKeyId: apiKeyId,
+                    userInfo: userInfo,
+                    cancellationToken: cancellationToken
+                );
+
+                //
+                return Ok(result);
+            }
+            catch (Exception ex)
+            {
+                //
+                var result = GetExceptionActionResult(ex);
+                return result;
+            }
         }
 
+        /// <summary>
+        /// Retrieve Specified Application's Api Keys ...
+        /// </summary>
+        /// <param name="applicationId"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
         [RequireXPowered]
         [Authorize(LocalApi.PolicyName)]
         [Authorize(Policy = XPolicies.EnabledUser)]
@@ -233,33 +309,176 @@ namespace xIds.Controllers
             CancellationToken cancellationToken = default
         )
         {
-            throw new NotImplementedException();            
+            //
+            try
+            {
+                //
+                // Validate ...
+                if (!applicationId.IsValidIntId())
+                {
+                    XException.InvalidArgs.Throw();
+                }
+
+                //
+                var userInfo = await GetUserInfo();
+
+                //
+                // Retrieve Application for Validating ...
+                var application = await provider.GetApplicationAsync(
+                    id: applicationId,
+                    userInfo: userInfo,
+                    includeBuilder: null,
+                    ignoreSoftDeleteds: true
+                );
+                if (application.IsNullOrDefault())
+                {
+                    XException.NotFound.Throw();
+                }
+
+                //
+                var result = await provider.GetApplicationApiKeys(
+                    userInfo: userInfo,
+                    applicationId: applicationId,
+                    cancellationToken: cancellationToken
+                );
+
+                //
+                return Ok(result.ToDynamicObject());
+            }
+            catch (Exception ex)
+            {
+                //
+                var result = GetExceptionActionResult(ex);
+                return result;
+            }
         }
 
+        /// <summary>
+        /// Retrieve Specified Api Keys Usages ...
+        /// </summary>
+        /// <param name="apiKeyId"></param>
+        /// <param name="applicationId"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
         [RequireXPowered]
         [Authorize(LocalApi.PolicyName)]
         [Authorize(Policy = XPolicies.EnabledUser)]
         [HttpPost("Applications/{applicationId}/ApiKeys/{apiKeyId}/Usages")]
-        public async Task<ActionResult<XApiKeyDto>> GetApiKeyUsages(
+        public async Task<ActionResult<IEnumerable<XApiKeyUsageDto>>> GetApiKeyUsages(
             [FromRoute] Guid apiKeyId,
             [FromRoute] int applicationId,
             CancellationToken cancellationToken = default
         )
         {
-            throw new NotImplementedException();            
-        }
-    
-        [RequireXPowered]
-        [Authorize(LocalApi.PolicyName)]
-        [HttpPost("Applications/{applicationId}/ApiKeys/{apiKeyId}/Validate")]
-        public async Task<ActionResult<XApiKeyDto>> ValidateApiKey(
-            [FromRoute] Guid apiKeyId,
-            [FromRoute] int applicationId,
-            CancellationToken cancellationToken = default
-        )
-        {
-            throw new NotImplementedException();            
+            //
+            try
+            {
+                //
+                // Validate ...
+                if (
+                    apiKeyId.IsDefaultGuid() ||
+                    !applicationId.IsValidIntId())
+                {
+                    XException.InvalidArgs.Throw();
+                }
+
+                //
+                var userInfo = await GetUserInfo();
+
+                //
+                // Retrieve Application for Validating ...
+                var application = await provider.GetApplicationAsync(
+                    id: applicationId,
+                    userInfo: userInfo,
+                    includeBuilder: null,
+                    ignoreSoftDeleteds: true
+                );
+                if (application.IsNullOrDefault())
+                {
+                    XException.NotFound.Throw();
+                }
+
+                //
+                // Retrieve ApiKey for Validating ...
+                var apiKey = await provider.GetApiKeyAsync(
+                    id: apiKeyId,
+                    userInfo: userInfo,
+                    includeBuilder: null,
+                    ignoreSoftDeleteds: true
+                );
+                if (application.IsNullOrDefault())
+                {
+                    XException.NotFound.Throw();
+                }
+
+                //
+                var result = await provider.FindManyApiKeyUsageAsync(
+                    userInfo: userInfo,
+                    includeBuilder: null,
+                    ignoreSoftDeleteds: true,
+                    cancellationToken: cancellationToken,
+                    predicate: x => x.ApiKeyId == apiKeyId,
+                    orderBuilder: x => x.OrderBy(y => y.RequestedOn)
+                );
+
+                //
+                return Ok(result.ToDynamicObject());
+            }
+            catch (Exception ex)
+            {
+                //
+                var result = GetExceptionActionResult(ex);
+                return result;
+            }
         }
 
+        /// <summary>
+        /// Validate Specifed Api Key ...
+        /// </summary>
+        /// <param name="request"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        [RequireXPowered]
+        [Authorize(LocalApi.PolicyName)]
+        [HttpPost("Applications/ApiKeys/Validate")]
+        public async Task<ActionResult<XApiKeyValidationResult>> ValidateApiKey(
+            [FromBody] XApiKeyValidationRequest request,
+            CancellationToken cancellationToken = default
+        )
+        {
+            //
+            try
+            {
+                //
+                // Validate ...
+                await ValidationProvider
+                    .GroupValidationBuilder()
+                    .AddNotNull(request)
+                    .AddNotEmpty(request.ApiKey)
+                    .AddNotEmpty(request.ClientIP)
+                    .ValidateGroupAsync();
+
+                //
+                var userInfo = await GetUserInfo();
+
+                //
+                var result = await provider.ValidateApiKey(
+                    userInfo: userInfo,
+                    apiKey: request.ApiKey,
+                    clientIP: request.ClientIP,
+                    requiredScope: request.RequiredScope,
+                    cancellationToken: cancellationToken
+                );
+
+                //
+                return Ok(result.ToDynamicObject());
+            }
+            catch (Exception ex)
+            {
+                //
+                var result = GetExceptionActionResult(ex);
+                return result;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/xIds.csproj b/xIds.csproj
index 1b4f73b..80fd750 100644
--- a/xIds.csproj
+++ b/xIds.csproj
@@ -29,13 +29,15 @@
 
   <!-- Local Dependencies -->
   <ItemGroup>
-    <PackageReference Include="xDashboard.xMessageService" Version="1.0.0" />
-    <PackageReference Include="xDashboard.xStorageService" Version="1.0.0" />
+    <!-- <PackageReference Include="xDashboard.xMessageService" Version="1.0.0" />
+    <PackageReference Include="xDashboard.xStorageService" Version="1.0.0" /> -->
   </ItemGroup>
 
   <!-- Project Dependencies -->
   <ItemGroup>
     <ProjectReference Include="..\Modules\xIdentityHelper\xIdentityHelper.csproj" />
+    <ProjectReference Include="..\Modules\xMessageService\xMessageService.csproj" />
+    <ProjectReference Include="..\Modules\xStorageService\xStorageService.csproj" />
     <ProjectReference Include="..\Modules\xIdentityService\xIdentityService.csproj" />
   </ItemGroup>