in turn affects health care costs. Calcium, vitamin D, and acid-base balance continued to dominate the discussion. The symposium offered an opportunity to learn about theories and data in nutritional research concerning bone as well as methodological approaches to cl- sify diets. The proceedings allow the reader to capture the new messages, to analyze the new scientifc data presented, and to use the book as a source of references in this feld. Peter Burckhardt Bess Dawson-Hughes Connie Weaver v Acknowledgments th This work comprises papers from the 7 International Symposium on Nutritional Aspects of Osteoporosis in 2009 in Lausanne, Switzerland.