This book sets out to provide a useful directory to writers, reviewers, and citizens interested in the environmental impact statement (EIS) process in the United States. Although several "environmental" directories address a narrow portion of EIS subject matter, there is no single directory that covers the wide range of agencies and organizations involved in the EIS process. Therefore, the purpose of this directory is to bring EIS-related agencies and organizations into one comprehensive reference book. EIS writing and reviewing can be improved by providing practioners with a directory that puts them quickly in touch with the national EIS net­ work. At the present time, practioners must rely on their personal, and sometimes, limited network of agencies and organizations for the exchange of information. The EIS Directory quickly connects EIS-related agencies and organizations throughout the United States at the national, regional, state, and local levels. The EIS Directory is a compilation of directories provided by members of the EIS community. A written survey of over five hundred agencies and or­ ganizations was made in 1980. The response to the survey provided a wide range of in-house directories. This book contains approximately 4, 000 entries developed from over 300 documents. This book was written in the hope that it will help people communicate more easi1y--u1timately improving the quality of EIS decision making. I re­ alize the limitations of this initial edition and accept the challenge of providing a more effective reference tool in future editions.