The use of video images in biomechanical analyses has become more realistic since the introduction of the shuttered video camera. Although recording rates are still limited to 60 Hz, exposure times can be reduced to prevent blurring in most situations. This paper presents a system for manually digitizing video images, a system that utilizes a video overlay board to place a set of cross hairs directly on a previously recorded or live video image. A cursor is used to move the cross hairs over required points. A BASIC program was written for a IBM PC-AT computer to accomplish this task. Video images of a known set of points were digitized, and calculated distances between points were compared to real distances. The mean of the observed errors was 0.79%. It was concluded that this digitizing system, within the limitations of video resolution, yielded digitizing errors similar in magnitude to those observed in cinematographic analyses.