SUMMARY - In order to gel a generai indication of thè extent of maedi-visna infection in dairy and meat sheep flocks in Italy, a wide serological survey covering flocks in several provinces was carried out in 1998. Blood samples were obtained through thè courtesy of veterinary surgeons involved in testing flocks for brucellosis. The recommendation given was to obtain blood samples from thè older ewes in thè flocks, though on a few occasions blood samples were received from sheep under two years old. On most farms about 10% of thè flock was bled. However if in thè sample of ewes tested no serological positive sheep were discovered, then a further group was bled until at least 75% of thè flock had been sampled or altematively at least one sheep had been detected with antibodies to MV virus. On receipt of thè blood samples sera were removed and store at -20°C lili tested. The test used was thè agar gel immunodiffusion test (AGID). The method adopted was that described by thè Ministry of Agriculture and Fisheries Central Veterinary Laboratory, Weybridge, UK. The survey covered flocks in 7 of thè 21 regions in Italy and from 1 ,to 27 farms according to thè region. Evidence of thè infection with MV virus was found in ali regions and thè number of farms with antibody positive sheep was from 1 to 20 (44-100%). A total of 1735 sheep were tested in 7 regions. The number tested on each farm varied from 1 to 100% partly according to thè size of thè flock. Antibodies were found in thè sera of 347 (20%) sheep.