Background: The Center for Medicare and Medicaid Innovation (CMMI)was established by section 1115A of the Social Security Act, which gave rise to the State Innovation Models (SIMs). Medicaid Integrated Purchasing for Physical and Behavioral Health, also known as Payment Model 1 (PM1), is a core payment redesign area of the Washington State Innovation Model project. Purpose: The aim of this study was expand understanding on the effects of the PM1 Initiative on Payer and Provider Organizations in the region through the lens of a conceptual framework. Methodology: The evaluation team conducted eight qualitative key informant interviews with twelve healthcare executives representing payers and providers engaging in PM1 under the SIM initiative. Results: Mapping results to an evidence-based conceptual framework shows emergent themes of care integration, connections to the Triple Aim, common facilitators and barriers of integration, and a potential concern for sustaining the initiative into the future. Conclusion: Evaluation of PM1 and clinical integration efforts requires extensive consideration of provider and managed care organization (MCO) needs and practice-based integration techniques. Integration evaluation depends on both internal and external contributing factors, which inform and guide changes to a focused evaluation framework. Practice implications: Future behavioral and physical health payment integration development in Washington state must consider the impacts on care coordination, partnerships, funding sources, and regional leadership to ensure sustainability of the payment model.