Using celebrities for promoting products is a popular advertising strategy. The selection of celebrity endorsers is of great concern to advertisers given the large sums of money to secure their participation. To date, most academic research on celebrity endorser effectiveness has focused on endorser characteristics (e.g., source credibility) or a match between a product and the endorser (e.g., match-up hypothesis). The study presented here introduces a new dimension for understanding celebrity endorser effects, the congruence between a consumer's perception of a celebrity's personality characteristics with the consumer's self-concept. Consumers’ self-concept is an important influence on purchase decisions (Ericksen, 1997; Graeff, 1996; Sirgy, 1982, 1985), and advertising has been viewed as the most effective tool for creating product images in relation to such self-concept (Sirgy, 1982). Drawn from the two streams of literature, this study proposes and tests an integrative model of celebrity endorsement by examining congruence effects of consumer self-concept and celebrity as well as product and celebrity. Results suggest that ideal congruity (congruence between consumers’ ideal self-image and celebrity image) adds explanatory power to a congruence model of celebrity endorser effects. Implications for advertisers and suggestions for future research are discussed.