This yearbook provides highlights of the work done by the various bureaus and offices of the Department of the Interior during 1970. The coverage is broad, relating to many aspects of conservation and the environment in the United States, in a descriptive, non-technical style. General theme of the report is the need for environmental management and the restoration and maintenance of an ecological balance. Topics considered include the fragile earth, individual responsibility for wise and prudent use of our land, re-creation of the man and land relationship, environmental research and repair work in replenishing the resources of our earth to counteract our explosive productivity, and the preservation of human heritage while developing and maintaining the quality of the natural environment. Numerous color photographs and art reproductions are presented throughout the yearbook. (BL)