Primary care in our current health system is fragmented, inefficient, and frequently unsafe. The proposed research entitled Ambulatory Care Compact to Organize Risk and Decision Decision-making (ACCORD) will design, develop, implement, and evaluate an innovative model of care delivery that enables patients and and primary care providers (PCPs) to agree upon shared, follow follow-up care plans that incorporate patient and provider preferences. This ?compact? between a patient and his or her own PCP will be supported by an information architecture and software designed to facilitate the creation, initiation, and longitudinal tracking of these preferred care plans. This proposal will test the following hypotheses: 1) Patients will partner with their PCPs to establish a clinical compact as an agreement to follow follow-up care plans in domains of preventive medicine, abnormal findings follow follow-up, and therapeutic drug monitoring;2) A clinical informatics architecture can be designed within an established PBRN to create and track these clinical compacts and to make visible any departures from plan;and 3) This patient patient-centered primary care model will result in better patient, provider, and quality of care outcomes compared to usual care. The impact of the ACCORD model on the patient?s experience of care and quality of preventive care will be evaluated in a randomized clinical trial of 12 primary care practices at Massachusetts General Hospital (MGH) within our Practice Practice-Based Research Network (PBRN) that serve a diverse patient population in Eastern Massachusetts.