Background: The goal of the Aging, Community and Health Research Unit (ACHRU) is to promote optimal aging at home for older adults with multimorbidity (≥2 chronic conditions) and to support their family/friend caregivers. This protocol paper reports the rationale and plan for this patient-oriented, cross-jurisdictional research program. Objectives: The objectives of the ACHRU research program are (i) to codesign integrated and person-centered interventions with older adults, family/friend caregivers, and providers; (ii) to examine the feasibility of newly designed interventions; (iii) to determine the intervention effectiveness on Triple Aim outcomes: health, patient/caregiver experience, and cost; (iv) to examine intervention context and implementation barriers and facilitators; (v) to use diverse integrated knowledge translation (IKT) strategies to engage knowledge users to support scalability and sustainability of effective interventions; and (vi) to build patient-oriented research capacity. Design: The research program was informed by the Knowledge-to-Action Framework and the Complexity Model. Six individual studies were conceptualized as integrated pieces of work. The results of the three initial descriptive studies will inform and be followed by three pragmatic randomized controlled trials. IKT and capacity building activities will be embedded in all six studies and tailored to the unique focus of each study. Conclusions: This research program will inform the development of effective and scalable person-centered interventions that are sustainable through interagency and intersectoral partnerships with community-based agencies, policy makers, and other health and social service agencies. Implementation of these interventions has the potential to transform health-care services and systems and improve the quality of life for older adults with multimorbidity and their caregivers. Trial registration: NCT02428387 (study 4), NCT02158741 (study 5), and NCT02209285 (study 6).