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Brown bears (Ursus arctos) in western and eastern Europe reportedly have different evolutionary histories. This finding is based on the occurrence of 2 distinct clades of mitochondrial DNA (mtDNA) genotypes in bear populations throughout Europe. Contact zones between populations of the 2 clades are found in Sweden and Romania. Patterns of variation below the species level raise the issue of what the unit of management should be. To investigate the nature of the contact zone in Romania, which contains both clades of mtDNA genotypes, we analyzed the spatial distribution of genotypes and the sex of the animals. One site in Romania contained individuals of both sexes that belong to either clade, thus excluding a spatial separation of individuals of different sexes from different clades. The maintenance of the contact zone is attributed to little female dispersal. Genetic data from small and endangered populations can be obtained non-invasively through the amplification from DNA sequences from excrement samples using the polymerase chain reaction (excremental PCR). Excremental PCR has provided important data on demography, genetic variability, phylogeny, and even feeding habits of the dwindling brown bear population of the Brenta Mountains in northern Italy's Trentino Province. These bears are members of the western clade and contain the same genotype as bears found in Slovenia, Bosnia, Croatia, and Romania. Restocking of the Brenta population is planned with bears from Slovenia. We analyzed genetic data of the European brown bear in terms of phylogeography and gene flow to provide a basis for management decisions.