Assessment of a computer-assisted learning (CAL) program dealing with designing removable partial dentures was performed as both formative and summative evaluation. Formative evaluation was obtained through open-ended questions in a written questionnaire administered to 60 junior students from two Australian Dental Schools and through observation of four groups of these students as they worked through the program. Formative evaluation, fundamental to completion of the program, led to several changes and additions. Observation of the students using the program during its final stages of development was one of the most informative and helpful parts of the evaluation. It allowed nuances of expression and body language to be noted that would not have been apparent in written or numerical data. Summative evaluation was obtained through structured questions in the questionnaire and through a post-CAL test under examination conditions. Summative assessment showed that students could attain a desired standard of knowledge if a lecture series was replaced by the CAL program; that the program was user-friendly, even for students with little or no computer experience; and that most students considered it to be a useful learning resource. More than half the students were concerned about using CAL to replace human instruction. It is significant that students were particularly impressed by aspects of the program that could not be duplicated by a book; the interactive nature of the learning process and the ability to rotate the diagnostic casts. This highlights the need for CAL programs to use the full potential of computer capability, rather than merely replicate a textbook on a screen.