A provisional list of all the endemic vascular plant genera in SW Asia is presented. The area, here defined to include Turkey, the Caucasus, N Iraq, Iran, Afghanistan and adjacent parts of Pakistan and Central Asia, has 161 genera restricted to it. By far, the greatest numbers of the endemic genera are in Apiaceae, Brassicaceae and Asteraceae; many are morphologically isolated and occur at random throughout the area. Non-endemic genera with relevant distributions in the area are also discussed, several having a major concentration in Central Asia/Afghanistan and radiate westwards from there reaching a limit in SE Turkey/N Iraq. Also in these and other non-endemic genera, there are many species confined to the west (Turkey) or the east (Afghanistan) but very few are distributed throughout. The paper attempts to provide a framework for future research. It draws attention to the need for a more precise terminology in discussing phytochoria and questions the validity of many currently widely used terms including Irano-Turanian.