A handle assembly for a delivery device the sequential release of trigger wires from a prosthesis to release the prosthesis from the delivery device. The handle assembly has two handles, one of which is a rotating handle. The rotating handle has a first and second trigger wire release mechanisms which operate to sequentially release a first and second trigger wire, respectively, and a locking mechanism. The other handle has a locking mechanism that prevents that operation of the second trigger wire release mechanism until the first trigger wire has been released.