Abstract
Institutional theory has become one of the main theories in management and organization studies. This chapter traces how institutional theory bears on research in corporate social responsibility (CSR). While providing an overview of diverse institutional studies of CSR, it also shows how institutional theory has moved from being used as an explanation for the (non-)adoption of and variation in CSR practices, to an overarching framework where CSR is understood as an institution that can be changed by different actors and institutional processes.