During the period 29 June to 2 July 1980, a Workshop was held at Timberline Lodge, Mt. Hood, Oregon, entitled "Vitamin B-6 Analyt­ ical Methodology and Criteria for Assessing Nutritional Status". The papers which follow are the proceedings of that Workshop and represent the combined works of 36 scientists from across the United States and Canada. In addition to the 19 papers, there were seven short presentations which we consider to be at the very frontiers of analytical methods and status assessment for vitamin B-6. These reports discussed such areas as production of specific antibodies to the various vitamers, the synthesis of deuterated vitamers, comparisons of ultraviolet, fluorescence and elctrochemical deter­ minations of the vitamers and the identification of polyamine­ pyridoxal Schiff bases in urine. Those reports are not included in this book solely due to their highly tentative and preliminary findings, not because we considered them of any less importance than the papers presented herein. In fact, these reports may well provide the foundations upon which subsequent workshops are devel­ oped. The feeling for the need of such a Workshop in part grew out of a previous workshop held at the Letterman Army Institute of Research, San Fra"ncisco, California, 11-12 June 1976.