The current study examined the effect of stereoscopic depth cues on vigilance performance and cerebral hemodynamics as reflected in cerebral bloodflow velocity (CBFV). During a 40 min continuous vigil, participants took the role of a flight engineer in a simulated fuel transfer task involving a circular gauge in which a vertical line was embedded. In a 2D condition, critical signals for detection were cases in which the vertical line was tilted slightly to the right. In a 3D condition, a stereoscopic display projected a 3D image in which critical signals were cases wherein the vertical line appeared to be located in front of the circular gage. The overall level of signal detections was greater in the 3D than in the 2D condition. Moreover, detection scores in the 2D condition showed the vigilance decrement, a temporal decline over time, while those in the 3D condition maintained relative stability. In both conditions, CBFV was greater in the right than in the left cerebral hemisphere and declined significantly over time. The results provide the the initial demonstration that 3D displays can enhance performance in tasks requiring sustained attention and that right hemispheric control may be involved in vigilance performance with both 2D and 3D stimuli.