The livers from 50 brown hares (Lepus europaeus) were examined by electron microscopy for calicivirus-like particles typical of the virus of European brown hare syndrome (EBHS). The virus was visible in 23 of the livers which included four taken from hares which died in 1982 and 1985 and which had been stored at -20 degrees C. The clinical histories, post mortem and other findings associated with these 23 hares were similar to those described in cases of European brown hare syndrome in other European countries. The findings were compared with those associated with viral haemorrhagic disease (VHD) of rabbits which, although it did not occur in the United Kingdom until 1992, is also caused by a calicivirus believed to be related to EBHS virus. The finding of the virus in hares which died from the disease in 1982 is the earliest recorded isolation of the organism and predates the description of VHD virus and VHD in China in 1984. A retrospective review of post mortem reports revealed cases of disease between 1976 and 1977 which may have been due to EBHS and it is considered that the disease has occurred sporadically in England for several years. The results from suspected and confirmed cases of EBHS in England between 1976 and 1990 are reported and the epidemiology and emergence of the disease is considered.