Holly Geyer, M.D., author of Ending the Crisis, is an Addiction Medicine Specialist at Mayo Clinic in Scottsdale, Ariz. Her work is directed toward helping people with complex illnesses who are in the hospital, with special attention to addiction screening, evaluation and treatment for patients and families with concerns about substance use disorder. A key part of her work focuses on quality of life and the best use of nondrug interventions for diseases such as cancer. In addition to her clinical activities, Dr. Geyer is active in research, patient advocacy and healthcare policy at an enterprise and state level. She is well published in high-impact scientific journals and book chapters and maintains an active international lecture schedule. She additionally serves as a Physician Director of the Mayo Clinic Physician Assistant Fellowship program.

Cassandra Clare is the author of the #1 New York Times, USA Today, Wall Street Journal, and Publishers Weekly bestselling Shadowhunter Chronicles. She is also the coauthor of the bestselling fantasy series Magisterium with Holly Black. The Shadowhunter Chronicles have been adapted as both a major motion picture and a television series. Her books have more than 50 million copies in print worldwide and have been translated into more than thirty-five languages. Cassandra lives in western Massachusetts with her husband and three fearsome cats.  Cassandra talked about the final book in her Last Hours trilogy, Chain of Thorns.