We all know it: The financial sector is bloated and banks are too big to fail. But just how bloated is it, and how much should it be shrunk? Gerald Epstein and his collaborator James Crotty use both micro and macro data to deliver the numbers. They build on James Tobin’s concept of functional efficiency to separate the financial sector’s beneficial activities (mobilizing savings, financing investment, and reducing risk) from its socially inefficient activities (gambling, and distorting the political process). An empirical study that is full of institutional detail and addresses the elephant in the room: big banks and regulatory capture — this is new economic thinking.