Markus J. Seibel completed a medical degree and a doctoral degree in 1984 from the University of Mainz, Germany and the University of Pennsylvania, Philadelphia. Since 1996, he has been the head of the Endocrine Laboratories at Heidelberg University, Germany and a consultant in Endocrinology. Since 1997, he has been an Associate Professor and Member of the Faculty of Medicine at the University of Heidelberg and as of 1999, he will be Associate to the Director of the Department of Endocrinology and Metabolism. His research interests include bone and cartilage metabolism, treatment of osteoporosis, and thyroid carcinoma. John P. Bilezikian, MD, the Dorothy L. and Daniel H. Silberberg Professor of Medicine and Professor of Pharmacology at the College of Physicians & Surgeons, Columbia University is Chief of the Division of Endocrinology and Director of the Metabolic Bone Diseases Program at Columbia University Medical Center. Dr. Bilezikian received his undergraduate training at Harvard College and his medical training at the College of Physicians & Surgeons. He completed four years of house staff training (internship, residency and Chief Residency) on the Medical Service at Columbia Presbyterian Medical Center. Dr. Bilezikian received his training in Metabolic Bone Diseases and in Endocrinology at the NIH in the Mineral Metabolism Branch under the tutelage of Dr. Gerald Aurbach. Dr. Bilezikian belongs to a number of professional societies including the American Society for Bone and Mineral Research, of which he served as President, 1995-1996 and the International Society of Clinical Densitometry, of which he served as President, 1999-2001. He serves on the Board of Governors of the International Osteoporosis Foundation (1998-present) and on its Committee of Scientific Advisors (2001-present). He is Chair of the Endocrine Fellows Foundation. He served as Editor-in-Chief of the Journal of Clinical Endocrinology and Metabolism (2000-2004) and as Senior Associate Editor of the Journal of Bone and Mineral Research (2008-2012). He is Executive Advisory Editor of Bone Research (2013-present). His books include Editor-in-Chief of The Parathyroids [1994, 2001, 2014], and co-editor of The Aging Skeleton (1999), Dynamics of Bone and Cartilage Metabolism (1999, 2006), Principles of Bone Biology (1996, 2002, 2008) and Osteoporosis in Men (2010). He served as co-chair of the last three NIH Workshops on Primary Hyperparathyroidism (2002, 2008, 2013). He is the recipient of the Distinguished Physician Award of the Endocrine Society, the Frederic C. Bartter Award of the American Society for Bone and Mineral Research (ASBMR) for Excellence in Clinical Research and the First Annual Global Leadership Award of the International Society of Clinical Densitometry. In 2009, he received the Gideon A. Rodan Excellence in Mentorship Award from the ASBMR. He received the Laureate Distinguished Educator Award of The Endocrine Society in 2014. In 2014, he was made honorary member of the Brazilian Society of Endocrinology and Metabolism. His publications number over 700.