This research delineates the effects of salespeople’s affective brand commitment on their brand sales effort by proposing an integrated model incorporating the Theory of Planned Behavior (TPB) and the Motivation, Opportunity, and Ability (MOA) Theory. Using survey data collected from 136 field salespeople, the authors demonstrate that affective brand commitment not only positively influences sales effort, but also mediates the effects of salespeople’s attitude, self-efficacy, and intrinsic motivation on brand sales effort. The study also identifies an interesting three-way interaction effect of affective brand commitment, self-efficacy, and intrinsic motivation on sales effort. These results provide important implications for sales managers to develop appropriate sales force recruitment, sales training, and coaching strategies in order to improve sales performance.