Immunotherapy for cytomegalovirus (CMV) infections is at a relatively early stage of development, with few clinical trials performed to date. However, considerable promise is being shown with immunoglobulin, monoclonal antibodies and the adoptive transfer of CMV-specific T-cell clones. In view of the many problems of current treatments for CMV infection, these new approaches are being pursued with interest. At the 4th Triennial Symposium ‘New Directions in Antivirals’ [San Francisco, US; November 1994], Dr Richard B Pollard from the University of Texas, US, discussed the potential, and the pitfalls, associated with immunotherapeutic strategies.