Our earlier study indicated that a group behavioral obesity treatment program delivered totally over the Internet produced clinically significant weight loss among overweight and obese individuals but the average weight losses were lower than those achieved with an in-person version of the same program. But online programs have the potential to reach a larger number of individuals, particularly those who cannot come into the clinical center for treatment on a weekly basis. Therefore, iReach2 seeks to determine strategies to enhance the weight loss outcomes of an effective online behavioral weight control program. The study will compare weight losses achieved with the online group program compared with the same program PLUS individual online Motivational Interviewing (MI) sessions. MI is a counseling style which seeks to strengthen personal motivation for and commitment to behavior change.At two study sites (Arkansas and Vermont) 398 overweight and obese adults were randomized to one of two interventions: (1) Internet intervention or 2) Internet intervention + MI. All participants received the same online 6-month, 24-session group-based behavioral weight loss program followed by 12 sessions of weight maintenance over the next year. The online program focuses on dietary and exercise habits and presents behavioral strategies to help initiate healthy habits and sustain them. Group synchronous chat allowed participants to learn strategies and support one another. Behavior change was added by online tools such as self-monitoring journals and lessons. Assessments were conducted every six months and included measures of body weight, adherence to treatment, motivational factors, website utilization, and treatment delivery cost.