A robot end effector exchange system comprises a movable robot arm and an end effector. Connecting structure on each of the arm and end effector are operable for releasably attaching the arm and end effector in an operative relationship. A fixture supportably receives the end effector attached to the robot arm and includes restraining structure operable for holding the end effector on the fixture to permit attachment and detachment of the end effector and the arm. Hydraulic actuators on the fixture selectively operate the connecting structure and the restraining structure.