diff --git a/Astral.ApiServer/Astral.ApiServer.csproj b/Astral.ApiServer/Astral.ApiServer.csproj
index 7f8c717..4b02de7 100644
--- a/Astral.ApiServer/Astral.ApiServer.csproj
+++ b/Astral.ApiServer/Astral.ApiServer.csproj
@@ -21,10 +21,6 @@
         <PackageReference Include="Swashbuckle.AspNetCore.SwaggerUI" Version="7.1.0"/>
     </ItemGroup>
 
-    <ItemGroup>
-        <Folder Include="Controllers\"/>
-    </ItemGroup>
-
     <ItemGroup>
         <ProjectReference Include="..\Astral.Services\Astral.Services.csproj"/>
     </ItemGroup>
diff --git a/Astral.ApiServer/Constants/OAuthGrantTypes.cs b/Astral.ApiServer/Constants/OAuthGrantTypes.cs
new file mode 100644
index 0000000..2e7c827
--- /dev/null
+++ b/Astral.ApiServer/Constants/OAuthGrantTypes.cs
@@ -0,0 +1,16 @@
+// <copyright file="OAuthGrantTypes.cs" company="alveus.dev">
+// Copyright (c) alveus.dev. All rights reserved. Licensed under the MIT License.
+// </copyright>
+
+namespace Astral.ApiServer.Constants;
+
+/// <summary>
+/// Available grant types for auth token requests.
+/// </summary>
+public static class OAuthGrantTypes
+{
+    /// <summary>
+    /// Password grant type.
+    /// </summary>
+    public const string Password = "password";
+}
diff --git a/Astral.ApiServer/Controllers/OAuthController.cs b/Astral.ApiServer/Controllers/OAuthController.cs
new file mode 100644
index 0000000..8c701e3
--- /dev/null
+++ b/Astral.ApiServer/Controllers/OAuthController.cs
@@ -0,0 +1,29 @@
+// <copyright file="OAuthController.cs" company="alveus.dev">
+// Copyright (c) alveus.dev. All rights reserved. Licensed under the MIT License.
+// </copyright>
+
+using Astral.ApiServer.Models;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+
+namespace Astral.ApiServer.Controllers;
+
+/// <summary>
+/// OAuth authentication controller.
+/// </summary>
+[Produces("application/json")]
+[Consumes("application/x-www-form-urlencoded")]
+[Route("oauth")]
+public class OAuthController : ControllerBase
+{
+    /// <summary>
+    /// Grant token request.
+    /// </summary>
+    /// <param name="tokenGrantRequest">Instance of <see cref="TokenGrantRequestModel"/>.</param>
+    [HttpPost("token")]
+    [AllowAnonymous]
+    public Task<IActionResult> GrantToken([FromForm] TokenGrantRequestModel tokenGrantRequest)
+    {
+        throw new NotImplementedException();
+    }
+}
diff --git a/Astral.ApiServer/Models/TokenGrantRequestModel.cs b/Astral.ApiServer/Models/TokenGrantRequestModel.cs
new file mode 100644
index 0000000..9c9104d
--- /dev/null
+++ b/Astral.ApiServer/Models/TokenGrantRequestModel.cs
@@ -0,0 +1,43 @@
+// <copyright file="TokenGrantRequestModel.cs" company="alveus.dev">
+// Copyright (c) alveus.dev. All rights reserved. Licensed under the MIT License.
+// </copyright>
+
+using Microsoft.AspNetCore.Mvc;
+
+namespace Astral.ApiServer.Models;
+
+/// <summary>
+/// Oauth token grant request.
+/// </summary>
+public class TokenGrantRequestModel
+{
+    /// <summary>
+    /// The grant type of the request.
+    /// </summary>
+    [FromForm(Name = "grant_type")]
+    public string GrantType { get; set; }
+
+    /// <summary>
+    /// Refresh token.
+    /// </summary>
+    [FromForm(Name = "refresh_token")]
+    public string RefreshToken { get; set; }
+
+    /// <summary>
+    /// Username.
+    /// </summary>
+    [FromForm(Name = "username")]
+    public string Username { get; set; }
+
+    /// <summary>
+    /// Password.
+    /// </summary>
+    [FromForm(Name = "password")]
+    public string Password { get; set; }
+
+    /// <summary>
+    /// Scope.
+    /// </summary>
+    [FromForm(Name = "scope")]
+    public string Scope { get; set; }
+}
diff --git a/Astral.ApiServer/Models/TokenGrantResponseModel.cs b/Astral.ApiServer/Models/TokenGrantResponseModel.cs
new file mode 100644
index 0000000..b36bf1f
--- /dev/null
+++ b/Astral.ApiServer/Models/TokenGrantResponseModel.cs
@@ -0,0 +1,37 @@
+// <copyright file="TokenGrantResponseModel.cs" company="alveus.dev">
+// Copyright (c) alveus.dev. All rights reserved. Licensed under the MIT License.
+// </copyright>
+
+using System.Text.Json.Serialization;
+
+namespace Astral.ApiServer.Models;
+
+/// <summary>
+/// OAuth Grant Request Response.
+/// </summary>
+public class TokenGrantResponseModel
+{
+    /// <summary>
+    /// The granted access token.
+    /// </summary>
+    [JsonPropertyName("access_token")]
+    public string AccessToken { get; set; }
+
+    /// <summary>
+    /// The granted refresh token.
+    /// </summary>
+    [JsonPropertyName("refresh_token")]
+    public string RefreshToken { get; set; }
+
+    /// <summary>
+    /// When it expires (ticks).
+    /// </summary>
+    [JsonPropertyName("expires_in")]
+    public long ExpiresIn { get; set; }
+
+    /// <summary>
+    /// Granted token type.
+    /// </summary>
+    [JsonPropertyName("token_type")]
+    public string TokenType { get; set; }
+}
diff --git a/Astral.Services/Services/UserService.cs b/Astral.Services/Services/UserService.cs
index 1b1d747..6828bd1 100644
--- a/Astral.Services/Services/UserService.cs
+++ b/Astral.Services/Services/UserService.cs
@@ -38,13 +38,13 @@ public class UserService : IUserService
     /// <summary>
     /// Initializes a new instance of the <see cref="UserService" /> class.
     /// </summary>
-    /// <param name="userRepository">Instance of <see cref="IUserRepository" />.</param>
-    /// <param name="cryptographyService">Instance of <see cref="ICryptographyService" />.</param>
-    /// <param name="userGroupService">Instance of <see cref="IUserGroupService" />.</param>
-    /// <param name="mapper">Instance of <see cref="IMapper" />.</param>
     /// <param name="createUserValidator">Instance of <see cref="CreateUserValidator" />.</param>
+    /// <param name="cryptographyService">Instance of <see cref="ICryptographyService" />.</param>
+    /// <param name="mapper">Instance of <see cref="IMapper" />.</param>
     /// <param name="registrationConfig">Instance of <see cref="IOptions{RegistrationOptions}" />.</param>
+    /// <param name="userGroupService">Instance of <see cref="IUserGroupService" />.</param>
     /// <param name="transactionProvider">Instance of <see cref="ITransactionProvider" />.</param>
+    /// <param name="userRepository">Instance of <see cref="IUserRepository" />.</param>
     /// <param name="userProfileRepository">Instance of <see cref="IUserProfileRepository" />.</param>
     /// <param name="logger">Instance of <see cref="ILogger" />.</param>
     public UserService(