diff --git a/Octokit.Reactive/Clients/IObservableRepoCollaboratorsClient.cs b/Octokit.Reactive/Clients/IObservableRepoCollaboratorsClient.cs
new file mode 100644
index 00000000..610c872d
--- /dev/null
+++ b/Octokit.Reactive/Clients/IObservableRepoCollaboratorsClient.cs
@@ -0,0 +1,44 @@
+using System;
+using System.Collections.Generic;
+using System.Reactive;
+
+namespace Octokit.Reactive
+{
+    public interface IObservableRepoCollaboratorsClient
+    {
+        /// <summary>
+        /// Gets all the available collaborators on this repo.
+        /// </summary>
+        /// <param name="owner">The owner of the repository</param>
+        /// <param name="name">The name of the repository</param>
+        /// <returns></returns>
+        IObservable<User> GetAll(string owner, string name);
+
+        /// <summary>
+        /// Checks to see if a user is an assignee for a repository.
+        /// </summary>
+        /// <param name="owner">The owner of the repository</param>
+        /// <param name="name">The name of the repository</param>
+        /// <param name="user">Username of the prospective collaborator</param>
+        /// <returns></returns>
+        IObservable<bool> IsCollaborator(string owner, string name, string user);
+
+        /// <summary>
+        /// Adds a user as a collaborator to a repository.
+        /// </summary>
+        /// <param name="owner">The owner of the repository</param>
+        /// <param name="name">The name of the repository</param>
+        /// <param name="user">Username of the prospective collaborator</param>
+        /// <returns></returns>
+        IObservable<Unit> Add(string owner, string name, string user);
+
+        /// <summary>
+        /// Removes a user as a collaborator for a repository.
+        /// </summary>
+        /// <param name="owner">The owner of the repository</param>
+        /// <param name="name">The name of the repository</param>
+        /// <param name="user">Username of the prospective collaborator</param>
+        /// <returns></returns>
+        IObservable<Unit> Delete(string owner, string name, string user);
+    }
+}