diff --git a/src/Orchard/Security/IAuthorizationService.cs b/src/Orchard/Security/IAuthorizationService.cs
index 85e7a9189..a85d1ebd5 100644
--- a/src/Orchard/Security/IAuthorizationService.cs
+++ b/src/Orchard/Security/IAuthorizationService.cs
@@ -1,6 +1,10 @@
 using Orchard.Security.Permissions;
 
 namespace Orchard.Security {
+    /// <summary>
+    /// Entry-point for configured authorization scheme. Role-based system
+    /// provided by default. 
+    /// </summary>
     public interface IAuthorizationService : IDependency {
         bool CheckAccess(IUser user, Permission permission);
     }
diff --git a/src/Orchard/Security/IUser.cs b/src/Orchard/Security/IUser.cs
index 2d69dfd0e..7bd273538 100644
--- a/src/Orchard/Security/IUser.cs
+++ b/src/Orchard/Security/IUser.cs
@@ -1,6 +1,9 @@
 using Orchard.Models;
 
 namespace Orchard.Security {
+    /// <summary>
+    /// Interface provided by the "user" model. 
+    /// </summary>
     public interface IUser : IModel {
         string Name { get; }
     }
diff --git a/src/Orchard/Security/Permissions/IPermissionProvider.cs b/src/Orchard/Security/Permissions/IPermissionProvider.cs
index 90b81b2ad..a6a48886a 100644
--- a/src/Orchard/Security/Permissions/IPermissionProvider.cs
+++ b/src/Orchard/Security/Permissions/IPermissionProvider.cs
@@ -1,6 +1,10 @@
 using System.Collections.Generic;
 
 namespace Orchard.Security.Permissions {
+    /// <summary>
+    /// Implemented by packages to enumerate the types of permissions
+    /// the which may be granted
+    /// </summary>
     public interface IPermissionProvider {
         string PackageName { get; }
         IEnumerable<Permission> GetPermissions();