Volunteer organizations face issues related to the retention of volunteers, not unlike those found in the paid workforce; however, management and authority structures and practices are different. In previous research, support factors and psychological contracts have been found to contribute to retention of employees. Few studies of volunteers have investigated the appropriateness of these variables. Survey data from 721 Australian volunteers from diverse organizations were analyzed to learn to what degree perceived organizational support, coworker support, and psychological contract breach explained volunteer intention to remain, having controlled for age and tenure. Psychological contract breach explained much more of the variance in volunteer intention to remain than tenure, coworker support, or perceived organizational support. The relationship between psychological contract breach and volunteer intention to remain is similar to that found in the paid workforce, despite the differences in management in the 2 sectors.