The Ad Hoc GFCM/ICCAT Working Group on Sustainable Bluefin Tuna Farming/Fattening Practices in the Mediterranean was set-up following a 2002 decision by the General Fisheries Commission for the Mediterranean (GFCM) which, in view of the expansion of bluefin tuna farming in the Mediterranean, decided that practical guidelines to ensure the sustainability of this activity were required. The work plan of the Working Group (WG) was discussed and proposed by a Coordinating Committee which met in January 2003 (Madrid, Spain) as agreed during the twenty-seventh session of the GFCM. At its first meeting (Rome, Italy, 12-14 May 2003) the WG produced a survey form that would enable to prepare a summary of the current situation of bluefin tuna farming in the Mediterranean, identify problem areas with respect to the issues to be addressed, and propose solutions. During the second meeting (Izmir, Turkey, 15-17 December 2003) the WG finalized a first snapshot on the current situation of bluefin tuna farming based on the information made available in the survey forms and progressed with the drafting of the guidelines. The summary snapshot consisted in three documents covering capture fisheries, farming and marketing/trade of bluefin tuna in the Mediterranean. The WG held its third and final meeting in Rome, Italy, from 16 to 18 March 2005. The meeting was attended by 19 experts representing 10 Mediterranean countries, Japan and the European Commission and, representatives from the Secretariats of the GFCM and the International Commission for the Conservation of Atlantic Tunas (ICCAT). The WG completed its mandate and finalized and adopted the "Guidelines on Sustainable Bluefin Tuna Farming Practices in the Mediterranean". Furthermore updated summaries on capture fisheries, farming and marketing/trade of bluefin tuna in the Mediterranean were also prepared by selected participants of the WG.