Regulatory impact analyses (RIAs) apply a well-established and widely-used framework for collecting, organizing, and evaluating data on the anticipated consequences of alternative policies. They help ensure that regulatory actions are justified and necessary to achieve social goals, and that these actions are implemented in the most efficient, least burdensome, and most cost-effective manner possible (OMB 2011a). To support these aims, RIAs include an assessment of the benefits and costs anticipated to result from a proposed regulatory action and from alternative policy options. They also address other impacts as required by law and executive order, to aid agencies and the general public in understanding the potential effects of regulatory decisions. To the extent possible, RIAs quantify and monetize the anticipated benefits and costs and assess the distribution of the impacts. This document provides guidance on best practices for regulatory impact analysis for HHS agencies.