Starch gel electrophoresis was used to genetic variation at 28 enzyme and protein within and between eight Southern African populations of mongooses Cynictis penicillata. Thirteen loci (46%) were polymorphic in one or more populations. Mean heterozygosity (H) was 3.4%. Allelic variation at all populations conformed 10 Hardy-Weinberg expectations and the mean value of Wrighi's F1s coefficient (0.039) indicated no evidence of inbreeding in populations. Owing to a high proportion of 'private' alleles (polymorphic alJeles occurring only in single populations), Wright's mean was exceptionally high for a mammal (0.585 for all populations, or 0.272 when samples wizh N <3 were excluded), indicating (P <0.01) spatial heterogeneity in allele frequencies. independent lines of evidence suggest thai low vagility in the species may contribute partly to the high result, although sampling error may also be implicated. The range of genetic distances between pairs of localities (0.000 - 0.105 for Nei's DN) was typical of conspeci/ic popUlations, and phenetic analysis of genetic distances failed 10 group popUlations on the basis of proposed subspeci/ic affiliation based 011 morphometric evidence.