Karyotypic descriptions are given of 16 species of Accipitridae new to cytology, viz. Torgos tracheliotus. For reasons of comparison the karyotypes are included of 5 species that have been previously studied, viz. Gypaetus barbatus, Haliaeetus albicilla, H. leucocephalus, H. vocifer and Pernis apivorus. All these species share the typical characteristics of the accipitrid karyotype, a moderate diploid number (66-72), the absence of large macrochromosomes, the presence of only 6-12 microchromosomes and a high number of mediumsized to small macrochromosomes. Differences exist in the numbers of biarmed and acrocentric autosomes and in the size and shape of a pair of typical satellited marker chromosomes.The karyological relationships in the Accipitridae are briefly discussed. On the basis of the morphology of the pair of satellited chromosomes (acrocentrics, subtelocentrics or microchromosomes) and the numbers of acrocentric elements nine possible phylogenies are constructed. When compared to conventional phylogenetic trees for the Accipitridae, the following points are remarkable in all possible karyological phylogenies: (1) the position of Pithecophaga is uncertain, it either represents an independent ancient lineage or is related to the Old World vultures; (2) Gypaetus probably is not related to the Old World vultures, it rather evolved from an ancester in common with the booted eagles; (3) genera like Buteo, Geranoaetus and Accipiter may have evolved independently from the booted eagles; and (4) the kites probably do not constitute a natural group.