A key problem for conservation is the coincidence of regions of high biodiversity with regions of high human impact. Twenty-five of the most threatened centers of plant diversity were identified by Myers et al., and these “hotspots” play a crucial role in international conservation strategies. The primary goal of the hotspots is to cover the most threatened centers of plant diversity, but their efficacy has not yet been tested empirically. For sub-Saharan Africa, our study evaluates the hotspots postulated by Myers and compares them to a set of redefined hotspots proposed on the basis of mapped distribution data for 5985 plant species. The two sets of hotspots overlap by 48%. Our redefined hotspots include 80% of the species and 66% of the range-restricted species of the sub-Saharan flora in areas under high humanimpact, whereas these values are 15% and 11% lower for Myers’s hotspots. Despite having equal size and a considerable spatial overlap with Myers’s hotspots, our redefined hotspots include further highly threatened centers of plant diversity in the Maputaland Pondoland Region, in Katanga, the East African Afromontane region, the Lower Guinea Region, and the Albertine Rift. Many of these redefined hotspots are poorly protected centers of plant and animal diversity. Their conservation is essential for a comprehensive coverage of Africa’s centers of biodiversity