Twenty-six papers in this volume provide a broad sweep of information on the geography, biodiversity and endemism of the highlands and escarpments of Angola and Namibia (HEAN). The original objectives of the project, which included the launch of field surveys, phylogenetic analyses and conservation strategies, were reduced by the constraints of the COVID-19 pandemic to a set of desk studies and syntheses on available information on the diversity and endemism of HEAN biota. The geographical delineation and characterisation of the HEAN and terms used in the volume are defined, and the challenges of limited information and an outline of the richness and endemism of taxa are presented. Current considerations on the origin and evolution of the biota are summarised based on the individual papers in the volume. It is concluded that despite the differing levels of taxonomic, geographic and phylogenetic understanding of the HEAN biota, sufficient information is available to recognise the HEAN as a regional zone of important biodiversity and endemism deserving of accelerated research activities and greatly increased conservation measures. Keywords: Angola, biological importance, escarpments, highlands, Namibia, synopsis.