M.Sc. / Imbrasia belina is a well-utilised natural resource in southern Africa. This resource can only be utilised sustainably after a thorough study of its ecology, breeding system and its genetic structures are assessed. The implementing of breeding programmes should be evaluated with well-defined management and conservation controls and regulations. The purpose of this study was to establish the amount of genetic variation and gene flow in two wild populations and the staggered generations of I. be/ina, and to determine which developmental stage should be used for further studies. Gene products of 41 protein-coding loci were analysed by horizontal starch gel electrophoresis. High levels of polymorphism (42% and 47%) and heterozygosity (0.182 to 0.21 0) were present in all groups. Results from initial studies indicated developmental constraints on the expression of several loci, namely CK, GPO and PEP-S. After further studies with larger sample sizes, it now appears that there are only allozyme and not isozyme differences between the individuals from the various developmental stages. The groups studied exhibit a large amount of variation within, but little differentiation and a large amount of gene flow between them. Results of the study indicate that the genetic diversity of I. be/ina populations is healthy. Thus, sustainable utilisation of the Messina Experimental farm (November/December) group is recommended due to the high heterozygosity and genetic variation in this population.