Instrument handles are adjustable relative to an end effector of the instrument. The handles may be releasably locked in selected positions and/or orientations relative to the end effector. When the lock is released, the handles may be moved to a different position and/or orientation relative to the end effector, and locked in place. The handles may pivot relative to the end effector around one or more joints. The handles may pivot about an axis of a hinge joint or a point of a ball and socket joint. The axis of the hinge joint may be aligned parallel or perpendicular to a center longitudinal axis of the end effector, or of a shaft between the handles and the end effector.