The document provides an overview of institutionalism. It defines institutions as patterns, norms, rules and schemes that govern social thought and action. Institutionalism aims to understand how these become embedded in social consciousness. It discusses isomorphism, by which institutions adopt similar forms to gain legitimacy and survival. There are three functions of isomorphism: coercive, through rules and laws; normative, through social obligations; and mimetic, through uncertainty. The document contrasts formal institutions, which are official rules from governments, and informal institutions, which are social practices. It provides examples of important theorists in institutionalism like David Mitrany, Jean Monnet, and Stephen Krasner. Finally, it outlines different types of institutionalism.