Governance is a word that is increasingly heard and read in modern times, be it corporate governance, global governance, or investment governance. Investment governance, the central concern of this modest volume, refers to the effective employment of resources—people, policies, processes, and systems—by an individual or governing body (the fiduciary or agent) seeking to fulfil their fiduciary duty to a principal (or beneficiary) in addressing an underlying investment challenge. Effective investment governance is an enabler of good stewardship, and for this reason it should, in our view, be of interest to all fiduciaries, no matter the size of the pool of assets or the nature of the beneficiaries. To emphasize the importance of effective investment governance and to demonstrate its flexibility across organization type, we consider our investment governance process within three contexts: defined contribution (DC) plans, defined benefit (DB) plans, and endowments and foundations (E&Fs). Since the financial crisis of 2007–2008, the financial sector’s place in the economy and its methods and ethics have (rightly, in many cases) been under scrutiny. Coupled with this theme, the task of investment governance is of increasing importance due to the sheer weight of money, the retirement savings gap, demographic trends, regulation and activism, and rising standards of behavior based on higher expectations from those fiduciaries serve. These trends are at the same time related and self-reinforcing. Having explored the why of investment governance, we dedicate the remainder of the book to the question of how to bring it to bear as an essential component of good fiduciary practice. At this point, the reader might expect investment professionals to launch into a discussion about an investment process focused on the best way to capture returns. We resist this temptation. Instead, we contend that achieving outcomes on behalf of beneficiaries is as much about managing risks as it is about capturing returns—and we mean “risks” broadly construed, not just fluctuations in asset values.