While the impact of tour guides' interpretation on tourism experience is well acknowledged, little research has been conducted on the production of effective interpretation by tour guides. In this study, effective interpretation is defined as producing a positive outcome on tourists' knowledge and understanding of the visited heritage site, feelings and emotion, satisfaction and likelihood of visiting other relevant nearby heritage sites. Based on a literature review, a conceptual model of effective interpretation consisting of four propositions was formulated and examined by empirical on-site research in the World Cultural Heritage Site in Macau. The empirical findings support the four propositions and the applicability of the model for effective interpretation in Macao. The research was conducted in two phases: on-site guide evaluation and a linked tourist survey. The target market was mainland Chinese visitors. The results revealed the influence of four factors on effective interpretation, namely, heritage and tourist information knowledge, service attitude, communication competence and emotional intelligence. Special attention is given to the use of humor, provocation and emotional sensitivity. Future research should further investigate tourists' emotion management and the applicability of this model to other tour guides' heritage interpretation, at different types of site and in different regions.