This essay studies a very large and important example of an environmental subsidy program — the Conservation Reserve Program (CRP). The CRP was introduced in 1985. It investigates how much less efficient, if any, a command-and-control (CAC) form of regulation would have been. That is, it seeks to assess the policy as implemented relative to a fundamentally different form of regulation — CAC. It then studies the ex post performance of this incentive-based instrument. In so doing, it provides information on the degree to which market-based incentive programs, as they have actually been implemented, have or have not lived up to the original optimism with which economists viewed such instruments.