hotodynamic therapy (PDT) promises to be a much better method in cancer treatment, compared to chemical procedures, due to its non-invasive character. Based on the combined effects of light and photoactive compounds – i.e. photosensitizers – it can be used for both detection and treatment of benign or malign tumors. The main advantage of this method is the use of optical techniques instead of the radiation classical methods, which can seriously harm the healthy tissue around the affected area. The present paper presents the most common techniques and photosensitizers used in PDT.