In the wake of the global financial crisis (GFC), many nations embarked on reform to the financial regulatory system. This reform, unprecedented in its scope, touched virtually every part of the financial system in the United States and Western Europe. This article summarizes the key reforms, explains how these reforms fit together, assesses the relevant scholarly literature, and suggests six significant areas of open questions for researchers. These six areas are ( a) liquidity rules, ( b) central clearing of swaps, ( c) shadow banking, ( d) lenders of last resort, ( e) extended guarantees, and ( f) resolution and restructuring.