Trypanosoma cruzi, the causative agent of Chagas disease, simultaneously expresses several different surface antigens. This contrasts sharply with blood-stream forms o f the African trypanosomes, which display only one variant surface glycoprotein at a time. Over the past few years, the genes coding for a number of T. cruzi proteins recognized by sera from patients have been cloned and at least partially sequenced. However, some of those discovered in more than one laboratory have been given different names. Here, Carlos Frasch, Juan Cazzulo, Lena Aslund and UIf Pettersson try to systematize the literature available on these antigens, including what is known about their localization and function.