This study investigates the relationship between leadership styles (e.g., taskoriented, relationship-oriented and participative leadership style), perceived control, psychological ownership of the job and several volunteers' work attitudes. Particular attention is given to turnover intentions, psychological withdrawal and senses of responsibility. Research participants were 162 volunteer workers from diverse occupational groups across 19 non profit organizations. Results of Persons correlations and mediated regression analyses demonstrated that (a) psychological ownership did not have relationships with turnover intentions and sense of responsibility but was significantly related to psychological withdrawal; (b) task-oriented, relationshiporiented and participative leadership style were positively related to perceived control, (c) perceived control was positively related to psychological ownership; (d) psychological ownership did not have mediating effects between perceived control and the volunteers' work attitudes; (e) perceived control only had a mediating effect between task-oriented leadership and psychological ownership. Recommendations for further research and implications for management are discussed in the final chapter.