Effective management of anthropogenic threats is key to sustaining biological diversity in protected areas. Types and distribution of threats to Bwindi Impenetrable National Park, Uganda were investigated to assess the Park's status 12 years after it was upgraded from a forest reserve to a national park. Bwindi, like many tropical forested parks, is surrounded by dense human populations. Threats were quantified in 104 1-km edge-interior transects set around the Park. The distribution of threats was patchy and was most common within 300–350 m of the edge. The commonest threat was harvesting of wood and poles. Other threats included occurrence of exotic species, degradation of adjacent habitat fragments and high impact of problem animals on some of the neighbouring communities. The fact that threats were primarily associated with the edges of the Park, when previously they were widespread throughout the Park, suggests that illegal resource harvesting has been reduced since the forest was upgraded to a national park. Park legislation, enforcement and related conservation efforts have been effective, and there should be increased effort to manage the people-park interface. Edge-based assessments appear to be useful for quantifying threats to protected areas and identifying areas in which they are concentrated.