A laser videodisc, holding 54,000 still frames per side, can be used to provide visual material of excellent quality for pathology teaching. In a collaborative project between ten pathology departments, the first pathology videodisc has recently been completed and the production of the disc is described. When used as illustrative material for computer-assisted learning programs, the videodisc offers accurate random access of still frames and allows the overlay of computer-generated graphics onto the video picture. This can be used to pre-identify every individual feature of a particular frame, and an example tutorial program is described to show how this may be used to improve the students' understanding of what they see. Details and costs are given for a workstation suitable for this application and potential future developments for this teaching method are discussed. Although objective assessment of the cost-effectiveness of interactive video in teaching pathology has yet to be undertaken, one suitably designed program can give individual tuition to many students, making this a most efficient use of teaching time.