The sparsity of Mesolithic sites preceding the earliest Neolithic in southeastern Europe has been variously attributed to lack of habitation, low population density, and biased research coverage. The question of whether some parts of the landscape were vacant, or whether the sites are there waiting to be found, has not been answered. This paper provides a land-use model for southeastern Europe that serves as an entry point for discussions about the presence and potential distribution of Mesolithic sites on the landscape. We use elevation and lithic raw material hotspots in key areas of southeastern Europe to build a set of expectations of where more sites might be found in countries where they are already known, and also build expectations for where new sites might be found across national borders where similar environmental conditions prevail. We also discuss potential strategies for prospective field survey in areas with no confirmed Mesolithic sites.