Methyl aminolaevulinate photodynamic therapy is increasingly practiced in the treatment of actinic keratoses, Bowen's disease and basal cell carcinomas. This method is particularly suitable for treating multiple lesions, field cancerization and lesions in areas where a good cosmetic outcome is of importance. Good treatment routines will contribute to a favourable result. The Norwegian photodynamic therapy (PDT) group consists of medical specialists with long and extensive PDT experience. With support in the literature, this group presents guidelines for the practical use of topical PDT in non-melanoma skin cancer.