Under the direction of Drs. A. Barlett, M.A. Serrano and J. Torrent, the round table The clinical trial as a cooperative task was held on May 24, 1991 in Barcelona. Dr. Antonio Esteve’s Monograph number 13 is published under the same name and with the same contents. Examples of submissions were: The clinical trial as a cooperative task; Role of the hospital pharmacist in the clinical trial; Good clinical practice regulations: role of the QAU; and Statistics in the clinical trial.