In the late 1960s there was great interest in the U.S. environmental field for duplicating the success economists had in developing statistical indicators. This article traces the history of the development of environmental indices at the Council on Environmental Quality from initial research aimed at preparing one or at best a few indices of environmental quality to the most recent effort which aims to organize indicators showing conditions and trends on a wide variety of environmental topics. The Council intends to distribute the findings periodically. The report may be viewed as a briefing book for policymakers. Criteria used in selecting and developing indicators —relevancy, selectivity, availability of data, changes over time, statistical quality, and scope of coverage — are discussed. A key purpose of this effort is to improve the quality of data available for making national environmental policies. Appendixes included are: (1) a bibliography of works dealing with the general problems of developing, using, and evaluating environmental indicators; (2) a selection of over 100 U.S. Federal periodical reponts on specific aspects of environmental conditions; and (3) a comprehensive framework for identifying topics and selecting meaningful and useful environmental indicators to be used as the report outline.