The last 20 years have seen rapid technological developments within the field of information technology. The internet, sophisticated software packages and increased accessibility to computers have all opened opportunities for educators. Against this background, increasing numbers of multimedia learning packages are available to the health professional. In this paper, Pirashanthie Vivekananda-Schmidt, Andrew Hassell and Monica McLean discuss the methodological issues relating to the evaluation of such multimedia based learning tools, using the example of a specific package, Virtual Rheumatology. They discuss the reasons for the increasing interest in the area of computer-based learning, the available evidence supporting the use of such tools in education, and issues about the design and production of this CD. They then discuss the evaluation of the package to illustrate the considerable methodological difficulties in the research and evaluation of Computer Assisted Learning (CAL) packages generally