The application of PDT in dermatology has been limited by technical problems, lack of standardized treatment parameters and controlled clinical trials, and cutaneous photosensitivity. PDT requires specially trained personnel and relies on devices that are expensive and difficult to maintain. In North America, PDT is currently performed at only a few centers on an investigational basis. Although a great deal of anecdotal clinical information is available on PDT for treating non-melanoma skin cancer, controlled trials are still needed in order to compare PDT with the highly effective methods already available. PDT may also be useful for a variety of nononcologic dermatoses. New photosensitizers such as BPD-MA, NPe6, and ALA offer the promise of causing significantly less prolonged photosensitivity than the currently available agents; combined with well-designed clinical studies, this will undoubtedly facilitate the acceptance of PDT into standard dermatologic practice.