We are pleased to present to our readers the Proceedings of the Fifth International Workshop on Phosphate and Other Minerals which was held in New York City, New York, U.S.A during September 23-27,1981. It was hosted by Joseph M. Letteri, M.D., Professor of Medicine at the State University of New York at Stonybrook School of Medicine, and Chief, Division of Nephrology, Nassau County Medical Center. As in the previous Workshops, this meeting provided an oppor tunity for interested scientists from interrelated fields, including nephrology, endocrinology, physiology, biochemistry and nutrition, to get together and discuss the recent advances in the field of phosphate and mineral metabolism. There were 29 invited presenta tions by leading scientists and 40 oral and 90 poster presentations selected from over 250 abstracts submitted to the Organizing Committee. The Workshop was attended by 250 scientists from 14 countries including Austria, Australia, Canada, Denmark, England, France, Germany, Holland, Israel, Italy, Japan, Sweden, and the United States of America. The Sixth International Workshop on Phosphate and Other Minerals will be held during June 24-26, 1983 in Verona, Italy. It will be hosted by Professor Giuseppe Maschio, Director, Division of Nephrology, Istituti Ospitalieri, Verona, Italy. The theme of this coming Workshop will continue to focus on the pathophysiology of phosphate homeostasis and the metabolism of other minerals.