Two experiments were conducted examining . three-dimensional pursuit tracking when operators of teleoperation simulations are faced with misalignment between the display and control frames of reference.Targets on the experimental displays moved irregularly in three dimensions and were tracked by subjects using either two 2-axis joysticks and a panelmounted perspective display or, in a separate experiment, a hand-mounted, 6 degree-of-freedom electromagnetic sensor and a head-mounted, virtual image, stereoscopic display..Analysis of the components of the tracking er-