Financial incentives for motivating changes in health behavior, for weight loss in obese individuals, are increasingly being tested by health insurers, employers, and government agencies. However, a key unanswered question regarding weight loss is how to structure these incentive programs to maximize their (1) effectiveness, underscored by the fact that most programs have not resulted in significant long-term weight loss; and (2) economic sustainability, as defined by their return on investment—a major factor in public and private decision-making. Obese patients represent an important population to target for effective weight loss interventions because they suffer from a high prevalence of serious obesity-related illnesses—including diabetes, hypertension, dyslipidemia, heart disease, stroke, sleep apnea, and cancer—disproportionately have a low socioeconomic status, and impose $147 billion in costs on the healthcare system annually. While prior studies testing financial incentives in this population have had variable short-term success and few have yielded long-term weight loss, a fundamental question remains unanswered and may partially explain variability in weight loss outcomes: specifically, it is unknown whether goal-directed incentives (incentives for achieving evidence-based, intermediate goals that increase weight loss but are underutilized, like dietary counseling, physical activity, behavioral self monitoring, and intensive weight management programs) or outcome-based incentives (like incentives for successfully losing weight) are more effective for promoting weight loss. Prior studies of weight loss incentives have largely emphasized only the latter. We propose a three-arm randomized controlled trial that will address this important knowledge gap among obese patients living in socioeconomically disadvantaged neighborhoods, with implications for other serious chronic health conditions. Comparing goal-directed incentives to outcome-based incentives and usual care, we will assess their impact on weight loss (≥5% of baseline weight), use of evidenced-based therapy, and quality of life, and evaluate their short-term and long-term return on investment.