Photodynamic therapy is a technique for administering a sensitizer, hematoporphyrin derivative, which is selectively retained in malignant tissue. This is then activated by light, usually of 630 nm resulting in selective deterioration of the malignant tissue. This technique has been used for detecting and treating a variety of cancers in experimental animals and human beings. In plastic surgery, it has been applied to both basal and squamous cell carcinomas as well as to other skin lesions. Metastatic deposits will also respond to this treatment. Advantages include ease of treatment, sometimes requiring little or no anesthesia, low incidence of reactions, ability to repeat the treatment any number of times, and sparing of normal tissue. Photodynamic therapy has been used as a salvage operation. to clear tissue of suspected or probable remaining malignant disease, and to alleviate the need for a radical operation, allowing a more conservative one. Photodynamic therapy continues to be an investigational tool, and it should be used only as an adjunct to commonly accepted techniques, and then only when needed. Common disadvantages include a severe photosensitivity of the patient for several weeks following administration of the drug as well as inability to treat adequately bulky tumors. New techniques of administration and methods of activation will make this an increasingly common and useful tool in the practice of plastic surgery.