This symposium was held at the l6lst ACS National Meeting, Los Angeles, March/April 1971. It represents a contribution to the discussion of problems connected with the state of water near macromolecules. Some papers are only peripheral to the problem of water structure but may become quite pertinent in specific cases. Questions concerned with water structure, rate of hydration, and similar problems are of importance for biological processes and are still not yet well understood. It is hoped that the papers presented here will be of some help in the clarification of problems in this area. H. H. G. Jellinek Department of Chemistry Clarkson College of Technology Potsdam, New York September, 1971 v CONTRIBUTORS S. Ablett, Unilever Research Laboratory, Colworth House, Sharnbrook, Bedford, England M. Anbar, Stanford Research Institute, Menlo Park, California F. W. Cope, Biochemistry Division, Aerospace Medical Research Laboratory, U. S. Naval Air Development Center, Warminster, Pennsylvania B. Crist, Camille Dreyfus Laboratory, Research Triangle Park, North Carolina F. Franks, Unilever Research Laboratory, Colworth House, Sharnbrook, Bedford, England H. R, Gloria, NASA-Ames Research Center, Moffett Field, California G. W. Gross, New Mexico Institute of Mining and Technology, Socorro, New Mexico H. R. Hansen, The Procter & Gamble Company, Miami Valley Laboratories, Cincinnati, Ohio R. S. Kaiser, Research Laboratories, Eastman Kodak Company, Rochester, New York N. Laiken, Department of Chemistry, The University of Oregon, Eugene, Oregon C. E. Lamaze, Camille Dreyfus Laboratory, Research Triangle Park, North Carolina G. N.