The main objectives of pituitary tumour treatment are to restore normal function of the pituitary gland and prevent tumour recurrences. In spite of the success of current therapies in the treatment of relatively small tumours, new therapeutic alternatives need to be explored for large invasive tumours, tumour recurrences postsurgery, and when intolerance to drug treatment develops. Gene therapy, which uses nucleic acids as drugs, is a very attractive alternative to classic therapeutic modalities. With the development of efficient gene delivery vectors, which allow widespread distribution and long-term transgene expression with limited side effects, the clinical implementation of gene therapy for the treatment of pituitary tumours will become a reality within the next five to ten years.