Two interactive, multi-media, virtual patient modules were designed and developed on compact disc (CD-ROM) as an instructional tool to address the need for dentists to increase their competence and comfort level in caring for individuals with developmental disabilities. Development teams consisting of pediatric and general dentistry faculty members, parents of children with developmental disabilities, an individual with a developmental disability, and educational specialists developed the two interactive, virtual patient cases. The first case involves a ten year old child with Down syndrome presenting with a painful tooth. The interactive case format requires dentists to make decisions regarding proper interactions with the child, as well as appropriate clinical procedures throughout the case. The second case focuses on communication issues involved in the delivery of care to an adult with deafblindness. The case/module format employs an Information Point, Decision Point, Video Demonstration instructional design. Effectiveness studies conducted with dental students from the University of Kentucky Dental College demonstrated significant student gains in both comfort and knowledge levels post module completion.