Researchers from Australia, Canada, China, Ecuador, and Mexico briefed participants about their research during the international session at the NIDA Clinical Trials Network (CTN) Steering Committee Meeting. The meeting was held April 15–16, 2015, in Gaithersburg, Maryland. INVEST/CTN fellow Chandra Jha, Ph.D., Australia, discussed his study of factors related to relapse among former and relapsed Nepali drug users, and how public health strategies can minimize relapse risks. His fellowship mentor is Dennis Donovan, Ph.D., University of Washington. INVEST/CTN Fellow Haifeng Jiang, M.D., China, described his learning process as he works with his fellowship mentor to conduct secondary data analysis and design a clinical trial to be conducted in his home country. Dr. Jiang’s mentor is Walter Ling, M.D., University of California, Los Angeles. Zunyou Wu, M.D., Ph.D., director of the National Center for AIDS/STD Control & Prevention at the Chinese Center for Disease Control and Prevention, reported on the status of CTN-0056, a cluster randomized trial investigating whether two interventions will improve linkages between HIV testing and care for people living with HIV in China. Nathalie Gendron, Ph.D., assistant director of the Institute of Neurosciences, Mental Health and Addiction at the Canadian Institutes of Health Research, discussed the new Canadian Research Initiative in Substance Misuse, which uses the CTN model to create teams of university researchers and community-based treatment providers. Clinical Trials Unit Coordinator Rodrigo Marin-Navarrete, Ph.D., Instituto Nacional de Psiquiatria Ramón de la Fuente of Mexico, presented the results of a cross-sectional study of co-occurring disorders among patients in residential addiction treatment centers. Petra Jacobs, M.D., reported on substance abuse treatment and research in Ecuador. Dr. Jacobs is a former assistant director of the NIDA CTN and was a 2002 NIDA Distinguished International Scientist and a 2001–2001 NIDA Hubert H. Humphrey Drug Abuse Research Fellow.