The Second Annual Report: Appendices to the Supplemental Volume provides detailed information about the data, methods, analyses, and findings from the independent evaluation of the first two years of CPC+ for the 2,905 practices in regions that began CPC+ in 2017. A full report on the evaluation of CPC+’s second year is found in the Independent Evaluation of Comprehensive Primary Care Plus (CPC+): Second Annual Report, which describes (1) engagement in CPC+ by payer partners and health IT vendors and participation by practices; (2) the supports practices received; (3) how practices implemented CPC+ and changed the way they delivered health care; and (4) the early impacts of CPC+ on cost, service use, limited claims-based quality-of-care outcomes, and patient experience for attributed Medicare fee-for-service beneficiaries. Additional detailed information can be found in the Second Annual Report: Supplemental Volume. An overview of findings from the Second Annual report is available in the two page Findings At a Glance.