Purpose Building on the attitude-behavior relationship model, this study aims to contribute to customer orientation literature by suggesting that service employees' commitment (i.e. personal attitude) affects their customer orientation via the effect of their participation in knowledge sharing with colleagues (i.e. employees' behavior). Design/methodology/approach The empirical analysis has been developed around survey data, collected from 165 service workers of Italian museums. The hypotheses are tested through the SPSS PROCESS macro plugin. Findings Drawing on the importance of human capital to tourism organizations, this study illustrates that affective commitment has a positive and significant influence on employees' customer orientation, and that this relationship is fully mediated by knowledge-sharing behaviors. Practical implications - As attitudes are more stable than behaviors, the findings suggest that managers of tourism organizations implement appropriate selection and recruitment techniques, together with adequate involvement and empowerment activities, to identify and support individuals whose attitudes fit the organizational goals. Originality/value Acknowledging the contribution that workers can give to service organizations' success, this paper enriches the understanding of the mechanisms that underlie the relationship between employees' attitudes and their orientation toward the customer. Building on the cognitive dissonance theory, it adds to extant research on the individual antecedents of employees' customer orientation by shedding light on the attitude-behavior relationship in tourism organizations.