When service providers regulate their moods and expressions (i.e., deep acting and surface acting), are they better performers? Drawing on the framework of activation-inhibition regulatory systems and regulatory fit, we propose (a) that deep acting represents an activation-oriented regulation strategy and surface acting, an inhibition-oriented regulation strategy; (b) that these strategies have separate pathways to desirable performance (i.e., affective delivery) and counterproductive performance (i.e., service sabotage), respectively; and (c) that performance is optimized when momentary regulation strategies are aligned with activation- and inhibition-oriented traits. Empirically, across two studies, we employ a multilevel approach (i.e., within- and between-person), a multisource approach (i.e., self, coworker, customer), and a multicontext approach (i.e., banks and restaurants) to test regulatory fit as applied to emotional labor. In two studies, we support separate activation and inhibition pathways, plus regulatory fit, in that deep acting is beneficial to affective delivery for those higher in two activation traits—namely, extraversion and openness—and that surface acting predicts service sabotage for those lower in an inhibition trait: conscientiousness. We empirically rule out mood as the explanation for these effects, propose future research to apply regulatory fit to other outcomes and contexts, and suggest practical implications for services.