The families Bach, Mozart and Strauss are known for music. Similarly, there are families known for their science. Among the more famous are the Huxley, Curie, and Bohr families. Another, not so well-known scientific family is that of the Krogh's of Denmark. August Krogh won the Nobel prize in physiology for his study of capillaries, but this work was only a small part of his many contributions to the field including pioneering studies of respiration in animals and man, in comparative physiology of osmoregulation, and in membrane transport. His wife, Marie Jorgensen Krogh, not only collaborated with her husband on many of his projects, but carried out independent research of her own including her classic study of the diffusion capacity of human lungs, other work in human physiology and nutrition. Their daughter, Bodil Schmidt-Nielsen, also became a successful scientist carrying out important research on kidney physiology and rising to become the president of the American Physiological Society. Though the Krogh family is not so well-known now, this situation seems likely to change. The daughter, Professor Schmidt-Nielsen, is undertaking with the support of this grant a scientific biography of her parents. Professor Schmidt-Nielsen brings unique qualifications to this study. As a physiologist herself, she thoroughly understands her parents work and can communicate with their students and friends. She knows Danish, and, because of her position, has special access to sources. Further, she has a sophisticated understanding of historical methodology which is rare among eminent scientists. She will examine vast amounts of archival material in the Royal Library in Copenhagen including personal family letters. She has already contacted and obtained materials from her parents collaborators and students. Her study promises to provide us with a classic study of the scientific enterprise from a very personal and intimately informed position. While such studies can be problematic at times, Professor Schmidt-Nielsen fully understands these problems and has demonstrated her ability to overcome them and write with real understanding about the scientific work of her parents. This study promises to be of great interest for historians, philosophers and biologists interested in the development of 20th century research.