This paper investigates public and private nonprofit employees’ motivation to serve the public and the public interest and variation in their perceptions of worker quality and work life in the public and business sectors. We propose a Model for Determinants of Sector Perceptions and propositions about the relationships between public service motivation, public sector motivation, private sector work experience, current work environment, and professional training and sector perceptions. The results point to the important relationships between professional training, work experience, public service motivation, and sector perceptions among public-serving individuals in the public and nonprofit sectors.