Abstract: A repetitive motion exercise therapy device is used to treat patients having stricken limbs. The exercise therapy device includes a frame assembly, a patient support assembly and a control system. The frame assembly includes at least one sub-assembly configured to support the arm of a patient. The at least one sub-assembly is configured to allow the patient arm to rotate about three shoulder axes of movement, an elbow axis of movement and three wrist axes of movement. A plurality of actuators are connected to the frame assembly. Each actuator is configured to move the sub-assembly, and therefore, the patient's arm, about one or more of the axes of movement. The patient support assembly is preferably height adjustable to allow patients of varying heights to be accommodated by the exercise therapy device. The control system preferably includes a user interface and a controller.