Regular physical activity is fundamental to wellbeing, but healthy habits can be difficult to create and maintain. Behavioral interventions delivered via conversational agents may offer a highly accessible and cost-efficient way to motivate individuals of all demographic groups to engage in physical activity. In this study, we will conduct a mixed-method systematic review and synthesis of existing literature on the use of conversational agents to promote physical activity. This review will provide insight into overall effectiveness of such conversational agents and elucidate successes and shortcomings of current interventions. This information will help guide the development of dialogue flows and program components for future conversational agents targeting physical activity. The objectives of our systematic review are to: 1. summarize the effectiveness of conversational agents designed to increase physical activity 2. describe conversational agent program characteristics (specifically, theoretical basis, treatment approach, and intervention techniques) 3. identify existing challenges, limitations, and/or gaps in the design and implementation of conversational flows for physical activity conversational agents.