The first Keystone Symposia on sirtuin biology, Sirtuins in Metabolism, Aging and Disease, held at Tahoe City, California, on February 12-16, 2012, was a great success with many positive feedbacks from attendees. The biology of sirtuins, a unique class of NAD+-dependent enzymes that modify diverse protein substrates, has rapidly emerged in the past decade as regulators of critical biological processes, and the field will further evolve into many interdisciplinary areas of biomedical science in coming years. Furthermore, sirtuins are now clearly recognized as important targets for preventive and therapeutic interventions against a wide variety of diseases. Therefore, this second symposium for sirtuin biology will particularly focus on integrative aspects of diverse sirtuin functions, featuring eight interdisciplinary sessions and one workshop. Because there is an increasing enthusiasm on sirtuin biology through the globe, it will be critical to provide such a forum where the significance of the “integrative biology of sirtuins” will be fully discussed and interdisciplinary interactions will be stimulated among people from many different fields. In this regard, this second Keystone Symposia meeting on Biology of Sirtuins will surely attract more diverse scientists from all over the world.