Dr. Martha Stipanuk is the James Jamison Professor in Nutrition in the Division of Nutritional Sciences at Cornell University, where she has been a faculty member since 1977. She received her B.S. from the University of Kentucky, her M.S. from Cornell University, and her Ph.D. from the University of Wisconsin-Madison in nutritional biochemistry. Dr. Stipanuk's professional career has focused on the study of amino acid metabolism, particularly the metabolism of the sulfur-containing amino acid cysteine. Her work has contributed to an understanding of the intermediary pathways of cysteine metabolism in mammalian cells and of the role of various tissues in cysteine metabolism, including glutathione synthesis and taurine production, within the whole body.