This study focuses on exploring the impact of social power on Organizational Citizenship Behaviour (OCB) and the role OCB may play as a mediator in the relationship between social power and personal and organizational effectiveness. Data were collected by administering self rated questionnaires to male middle level executives (N = 250) based in motor cycle manufacturing organizations based in northern India. The mediator analysis illustrates that all the fit indexes were in an acceptable range which indicates that OCB has mediated significantly between social power and effectiveness. Other results as analyzed through multiple regression analysis demonstrate the significant impact of social power on individual dimensions of OCB and effectiveness. With the aim of advancing research on the concepts of OCB and social power from an Indian work context, this study highlights the potential benefits to managers of using positive forms of social power as part of their managerial style in order to enhance OCB and in turn increase personal and organizational effectiveness.