Forty-nine Trypanozoon stocks isolated from camels in five different areas of Kenya were screened for isoenzyme patterns of 11 enzymes using thin-layer starch gel electrophoresis. The results were compared with those obtained in other studies with Trypanosoma (Trypanozoon) evansi stocks from South America, Nigeria, Sudan and Kuwait. Most of the Kenyan camel stocks were found to be either identical or closely similar to T (T) evansi stocks from elsewhere and were therefore designated T (T) evansi also; these Kenyan stocks grew well in rats and were monomorphic. However, four other Kenyan stocks were electrophoretically distinct, and one of them showed marked pleomorphism in rat blood; this latter stock was shown to be tsetse transmissible and was therefore designated T (T) brucei.