This paper describes findings from two studies which examined relationships among social processes of leadership, organisational commitment, citizenship behaviours and organisational effectiveness within the Australian public sector. Data analysis using structural equation modelling indicated significant relationships between social processes of leadership and all criterion variables. Findings from the first study indicated that social processes of leadership were associated with significantly higher organisational effectiveness, organisational commitment, organisational citizenship behaviours, and overall organisational effectiveness. In the second study, components of social processes of leadership were associated with significantly higher organisational effectiveness. Theoretical and managerial implications following on from this study are discussed.