This study was started as a revision of the Malaysian species of Neckeropsis, but soon it proved to be necessary to include the species from the adjacent areas. The result was a revision covering all Asiatic and Pacific species. The material studied was obtained from the following herbaria (abbreviations according to Index Herbariorum I, ed. 4, 1959): BISH, BM, BO, BR, BRI, FH, G, GL, GRO, H, K, L, M, MEL, NICH, NSW, NY, PC, PNH, SAN, SING, US.