New University of Georgia research shows that while on the job, public servants contribute not just to mandated sustainability but also to discretionary eco-friendly initiatives of their own. "Some people are born with a higher intrinsic need to serve the public," said study co-author Robert K. Christensen, an associate professor in the School of Public and International Affairs. "They have a desire to help others and serve society. Government and nonprofit managers, for example, typically have higher levels of public service motivation than business managers.