This graduation project is based on the design brief where Microsoft identifies durability issues with its Xbox One controller. During the project a modular controller was developed. The design of the modular controller consists of 4 interchangeable parts, each sliding into one of the four designated areas located on the top side of the Modular controller. These areas are currently used as the two thumbsticks, the D-pad and the XYBA buttons. By making use of identical module housings and connections these modules become fully interchangeable. This allows the users to customize their controller's button layout as they prefer. The modules will also be sold separately, further allowing customization and replacement of failed or broken parts and adding later developed modules as well. This supports the circular product design theory by increasing the lifespan and personal attachment towards the controller.