This paper outlines the extraordinarily rich diversity of biomes and ecoregions found within the highlands and escarpments of Angola and Namibia (HEAN). Across 2,700 km of latitude, the climate ranges from tropical summer rainfall averaging at 1,200 mm per year in the north to warm temperate non-seasonal rainfall of 100 mm per year in the extreme southwest. Biomes range from Guinea-Congolian rainforests, Afromontane forests and grasslands, arid and mesic savannas and woodlands, to the Namib Desert. The concepts of biomes, ecoregions and endemism are discussed, and these terms applied to the four biomes and twelve ecoregions falling within the HEAN. Keywords: Angola, biomes, ecoregions, escarpments, highlands, Namibia, vegetation types.