This study examined whether perceived behavioural control predicted the intention to use condoms at next sexual intercourse above the components of the theory of reasoned action, as well as the sufficiency of the theory of planned behaviour (TPB) as a theory of intention among Tanzanian adolescents. Five hundred and twenty-eight students who were sexually active, from seven secondary schools in Arusha, Northern Tanzania, completed a questionnaire designed to measure the components of the TPB. Behavioural intentions were significantly predictable from attitudes (.11), subjective norms (.22) and perceived behavioural control (.48). The inclusion of past behaviour into the regression equation increased R(2) only marginally (2 percent) but significantly, suggesting that the TPB provides a fairly accurate explanation of intention to use condoms among Tanzanian adolescents. The implications of this finding in relation to theoretical and practical issues are discussed.