Volume I: An intellectual autobiography rather than a narrative of a life and career, including answers to questions submitted by friends, associates and peers in addition to those posed by the interviewer; material on early family background, education, early professional experience in Maryland State Health Department, as teacher and editor. Major issues discussed on municipal, state, regional, national and international levels: linkage of engineering and health, methods of water purification, environmental groups and pressures, water fluoridation, duplicate systems, problems of small municipal water systems, waste water re-use, separation of investigatory responsibility and regulatory responsibility, evaluation and role of state health agencies, radioactive waste disposal problems, controlled procedure for chlorination of water, generalized law on performance of filtration, total approach to environmental aspects, national management of water resources, long range planning, gradualism and compromise in operation, disposal of non-radioactive wastes, water development in Israel, flood protection, irrigation, decision making in less developed countries, speed of cultural change; vignettes and anecdotes of leading figures in many areas. Volume II: Continuation of his intellectual autobiography, including questions from associates as well as from the interviewer. Major issues discussed on municipal, regional, national, and international levels include: irrigation in less developed countries and lack of professional manpower; responsibility of Congress, administrative agencies, and the media for environmental protection rules and issues; his role as teacher: style and methodology, gratifications, relationship with University administration, faculty, students; biostatistics and epidemiology; Jewish identity; chemical dumping, disposal of hazardous wastes, recycling; bank erosion. Discussion of his contributions to World Health Organization, World War II, Maryland State Planning Commission, City of Baltimore, National Resources Planning Board, National Water Resources. Comments on dysentery epidemic, Chicago World's Fair, 1933; Klaus Fuchs; Three Mile Island. Discussion of major challenges, accomplishments, and disappointments; comments on Franklin D. Roosevelt, Harold Ickes, other public figures.