Working closely with The Six-Foundation Collaborative, Avalere Health will design a survey instrument to capture the extent to which Medicare Advantage (MA) plans have adopted evidence-based interventions for complex populations and pilot the survey in three markets of differing size, geography and provider risk. The project includes four tasks: 1) building a sampling frame, 2) developing the survey instrument, 3) administering survey and conducting analysis, and 4) developing a final report with input from an advisory council to discuss high-level findings. The key target respondent in each plan will be the chief medical officer and/or population health officer responsible for plans within the selected market. This project will inform the feasibility of a second phase of work to conduct a national survey of MA plans in order to assess the extent evidence-based approaches and models have been adopted to meet the needs of complex adults.