The D.C. Circuit’s Homer City decision doesn’t eliminate the uncertainty about environmental regulations that has vexed public utility commissions, the utilities they regulate, and the investment community for more than a decade. At a minimum, it extends that uncertainty farther into the future, and arguably adds new levels of uncertainty where issues had largely been resolved. No regrets, risk-reducing solutions—incorporating energy efficiency and demand response, including clean distributed generation—can cut through the fog of uncertainty and serve the public interest regardless of how these issues unfold. In the wake of Homer City, these risk-mitigation concepts make as much sense today as they did before the D.C. Circuit issued its CSAPR decision. In this article, published by Public Utilities Fortnightly, RAP explores least-risk planning opportunities aimed at reducing the impact of regulatory uncertainty.