This 4-month randomized controlled trial is designed to investigate the short-term efficacy and feasibility of a novel, social support-enhanced behavioral weight control intervention. Participants will be recruited via email listservs, fliers, and word of mouth. They will be randomized to a standard behavioral weight control treatment (SBT) or a social support-enhanced behavioral weight control treatment which receives the same intervention as SBT plus social support resources (specifically, additional self-monitoring technologies) for weight loss.