This paper advances knowledge on how the forms of institutional logics that emerge and become venerated among members of a singular organization in a heterogeneous field are influenced by struggles between contending interest groups. It examines the moderating effect of group dynamics that occur when an organization attempts to balance novel institutional complexity within organizational bounds through its hiring and promotion systems. The authors argue that, while the specific institutional oppositions of heterogeneous fields compel organizational changes, the institutional forms that emerge and become legitimate among members of an organization in such fields are the effects of indeterminate social processes of regularization and breaking of coexisting logics. The paper provides insights into how the negotiations among groups of organizational actors over the process and outcome of institutional change are influenced by asymmetric power relationships yet significantly mediated by their social strategies. The findings reported are from an ethnography of the enactment of institutional changes at a South Korean credit card company following the economic crisis in 1997 and the International Monetary Fund bailout programme.