Two experiments (N = 116) explored the effects of evaluative conditioning on mature brands. Explicit attitudes for mature brands were unaffected by evaluative conditioning. Experiment 1 showed, however, that evaluative conditioning changed implicit attitudes toward Coke and Pepsi. This occurred only for participants who initially had no strong preference for either brand. Contingency awareness was not necessary to change Implicit brand attitudes. Experiment 2 showed that brand choice was related to the altered implicit attitudes, but only when choice was made under cognitive load. Implications of these data for evaluative conditioning specifically, and for consumer research in general, are considered.