This article investigates the antecedents and consequences of source credibility within the context of the relatively new but growing phenomenon of Chief Executive Officer (CEO) endorsers. The study results indicate that source credibility is a central determinant of a CEO endorsers' ability to effect desired outcome states. Results also indicate that the effect of message source credibility on purchase intentions, though strong, is not direct because beliefs about critical product attributes mediate the effect of a message source's credibility on behavioural intentions. The results of the study also indicate that models of source credibility derived from the celebrity endorser literature do not generalize to the CEO endorser context. Specifically, the attractiveness and expertise of the message source had no significant impact on receivers' perceptions of credibility.