Evidence indicates that sugar-sweetened beverage (SSB) taxes may reduce rates of childhood obesity, particularly among high-risk populations. However, state and local efforts to enact SSB taxes have been unsuccessful, and public opinion research indicates limited support for these policies. Enactment of SSB taxes will be unlikely without public support, yet little research is available to assess how to effectively frame these policies. To address these issues, this study will: 1) identify appropriate message frames, by conducting interviews with SSB tax advocates in two settings where legislation was recently defeated (Philadelphia and New York state) to identify emerging pro- and anti-tax arguments used in recent debates and identify subjective assessments of how message framing shaped prior policy debates, and 2) test message frames, by conducting a randomized longitudinal message framing experiment to test empirically how arguments for and against SSB taxes affect policy attitudes overall and within key subgroups, with the goal of identifying the most resilient messages to be deployed in future SSB tax policy debates.