An epidemiological study was carried out from September 1992 to September 1993 on 78 nursing ewe flocks in the south of France. From the data base consisting of 476 cases of clinical udder disease, a typology was realised, based on Multiple Correspondence Analysis and Hierarchical Ascending Clustering. The main characteristics of the 5 types of disease that have been found are the following: Type 1 (n=140): transitory increase of the size of the whole udder, bilateral persistent agalactia. Type 2 (n=50): decreased size of the affected half-udder, unilateral persistent agalactia. Type 3 (n=75): unilateral and transitory agalactia only. Type 4 (n=80): unilateral and transitory increase of the size of a half-udder. Type 5 (n=131): unilateral and persistent affection, the half udder being hot or cold, red or purplish with increased size, modified milk and behaviour of the ewe affected. The use of the clustering method and the interpretation of the 5 types are discussed