Julia Harfin is Professor and Chair of the Orthodontic Department at the School of Dentistry, Maimónides University, Buenos Aires, Argentina. Dr. Harfin has served as the president of various organizations: the Argentine Society of Orthodontics (1990–6), ALADO (1999–2008), the Argentine Chapter of the International College of Dentists (1997–2001), the Argentine chapter of the Pierre Fauchard Academy (1992–1993), and the International College of Dentists Section IV (2010–2). She was a member of the Executive Committee of the World Federation of Orthodontists from 2000 to 2010. She is an Honorary Member of the Argentine, Chilean, and Polish Orthodontic Societies and in 2010 became a member of the National Academy of Dentistry. Also in 2010 she was named Woman of the Year in Medicine and Healthcare. Dr. Harfin is the author or editor of several previous books, including Achieving Clinical Success in Lingual Orthodontics (Springer, 2014).Somchai Satravaha isClinical Associate Professor at Mahidol University, Bangkok, Thailand and a Diplomate of the Thai Board of Orthodontics. She received her DDS (Hons) from Chulalongkorn University, Bangkok and later earned the qualification of Zahnärztin für Kieferorthopädie (Orthodontist) from Baden-Württemberg, Germany and Dr. med. dent. (magna cum laude) from Munich, Germany. Dr. Satravaha served as an executive committee member of the World Federation of Orthodontists from 2005 to 2015 and is a past president of both the Thai Association of Orthodontists and the Asian Pacific Orthodontic Society. She received a Lifetime Achievement Award from the Thai Association of Orthodontists in 2013 and was a recipient of an Outstanding Alumni Award from Chulalongkorn University Dental Alumni Association in 2014. She is an honorary member of the Association of Philippine Orthodontists and current president of the Advisory Board of the Thai Association of Orthodontists.Kurt Faltin Jr. has been Full Professor in Orthodontics at the University Paulista – UNIP, São Paulo, Brazil since 1982, where he is currently Chairperson of the Department of Orthodontics. He was previously Full Professor in Orthodontics at the University of Mogi das Cruzes, Brazil (1971–86). Dr. Faltin is also an Invited Professor at the Facial Orthopedic Department at the University of Ulm in Germany. He is current President of the Brazilian Association of Orthodontics and Facial Orthopedics, and past president of ALADO and member of the Executive Committee of the World Federation of Orthodontists. Dr. Faltin is an Honorary Fellow of the German Association of Orthodontics (Deutsche Gesellschaft für Kieferorthopädie) and of the Orthodontic Societies of Peru and Mexico. He teaches in the main orthodontic societies within and beyond Brazil and is the author of numerous scientific papers and book chapters.