The U.S. Environmental Protection Agency's (EPA's) Office of Ground Water and Drinking Water developed this document to provide information to stakeholders and other interested parties on analyzing the effects of regulations establishing Maximum Contaminant Levels (MCLs) for drinking water. EPA created this document in response to new provisions contained in the 1996 Amendments to the Safe Drinking Water Act (SDWA), working closely with a group of stakeholders -- the Benefits Working Group of the National Drinking Water Advisory Council. The Amendments create specific requirements for assessing benefits and for using the resulting information in EPA decision-making. This document focuses on the benefits valuation issues commonly addressed by EPA's economists and policy analysts. We also briefly discuss the assessment of costs and risks, and provide references for more detailed information on these topics. In addition to SDWA's statutory provisions, regulatory benefit-cost analyses conducted by the Federal government are subject to several other sets of requirements. Chief among these are guidelines developed by the U.S. Office of Management and Budget for all Federal agencies and guidance developed by EPA for its own programs. These documents require analysts to adhere to best practices as defined by the economics profession, and emphasize the need to clearly communicate (1) the rationale for decisions made in the course of the analysis; (2) the implications of the findings; and (3) the uncertainties in the resulting estimates. Regulatory analyses also comply with several statutory and administrative requirements for addressing impacts on selected groups, including small businesses and government units, low income and minority populations (i.e., environmental justice), and children. This document is based on, and consistent with, these sources of requirements for regulatory analyses.