Affiliate marketing is a prominent, contemporary type of performance-based Internet marketing whereby a company compensates affiliates for each customer referred through the affiliate’s marketing efforts. It is regarded as one of the most promising customer acquisition tools in eTourism. The present study aims to identify the key variables affecting consumer trust in tourism-related affiliate websites. A mixed method approach was adopted to explore both the consumers’ perspective, via focus-group interviews, and that of tourism affiliate practitioners via an online questionnaire. The main findings suggest that there is a distinction between pivotal determinants of trust and trust-enhancing factors. It is suggested that affiliates need to expose their competence and integrity to consumers. Affiliates that feature integrated booking engines need to reduce consumer’s uncertainty by structural assurances and by providing background information on their websites.