In order to reach an estimate of the amount of gill-net set, potential sources of information are reviewed. The principal enmeshing gears in Irish waters are briefly described. The following sources of information are examined on the extent of the fishery: salmon drift net licence sales figures, the register of fishing vessels, The European Communities' Logbook and, of greatest value, a survey of gears in use carried out in 1991. Additional information is supplied on sales of netting and on landings by gill net, the latter based mainly on limited sampling data. The total length of large mesh bottom-set gill net is calculated as 100,000 km days annually.