Organizational citizenship behaviour has generally been associated with organizational effectiveness. However, recent research has shown that this may not always be the case and that certain types of organizational citizenship behaviour such as compulsory citizenship behaviour, may be inimical to the fulfillment of formal goals and organizational effectiveness. Using military historical and business organizational secondary data, the paper maintains that extreme variance in either organizational (task) or personal (social psychological) support organizational citizenship behaviour generates entropic citizenship behaviour which derails completely the effective accomplishment of formal organizational goals. A general model of organizational citizenship behaviour with entropic citizenship behavior as its novel conceptual boundary is developed in the paper, and four specific propositions with implications for future empirical research are delineated.