Since the 1980s, institutional investors have increased their assets under management enormously. Additionally, many institutional investors have pushed for an alignment of interests between managers and shareholders through stock-based forms of remuneration, thus reinforcing the financialization of listed corporations. This chapter seeks to contribute to exposing the power relations that underlie and drive the process of corporate financialization in many countries, and show how these relations have changed over time. It deals with a brief overview of the emergence of institutional investors and of equity markets in general as the former are inextricably linked to the latter. Institutional investors can have different legal forms and follow diverse investment strategies, what they have in common is that they are “intermediary investors” – they are institutions that manage other people’s money. During the 1970s, institutional investors were quite small in absolute and relative terms.