How should we regulate the derivatives markets? Dodd-Frank gave the CFTC (and SEC, for securities derivatives) the power to act. But how should they act? Again, Dodd-Frank offered guidance, but the terms of regulation, in particular of the clearinghouses that are supposed to centralize derivatives trading has been set not by statute, or by CFTC rule, but by a just-concluded agreement with European regulators on how to oversee the market. That's increasingly how capital markets regulation works, given the mobility of capital and need for standardization. But it is certainly idiosyncratic, both as a method of domestic regulation and international governance, because it constitutes rule by agreement, not by law, which is something I've written about in the past.