What regulatory approach best fosters commercial innovation? Traditionally, it had been thought that ex post, decentralized approaches that exploit private attorney generals like the common law were best, but many business interests today advocate ex ante, centralized, public sector approaches like federal statutes or federal rulemakings that preempt the common law. This panel will explore which attributes of regulation best serve innovation: ex ante or ex post? Decentralized or centralized? Public sector or private sector? -- This panel was presented during the Fourth Annual Executive Branch Review Conference on May 17, 2016, at the Mayflower Hotel in Washington, DC. -- Featuring: Prof. Brian T. Fitzpatrick, Professor of Law, Vanderbilt University Law School; Prof. Brian Galle, Georgetown University Law Center; Prof. Michael S. Greve, Professor of Law, Antonin Scalia Law School, George Mason University; and Mr. Adam Thierer, Senior Research Fellow, Mercatus Center, George Mason University. Moderator: Hon. Rachel Brand, Chairman, Litigation Practice Group.