Background:Patient engagement is a priority for health care quality improvement and health system design, but many organizations struggle to engage patients meaningfully. We describe patient engagement activities and success factors that influence organizational decision-making in Ontario’s patient medical homes.Methods:From March to May 2018, we conducted an online survey focused on practice-level patient engagement that targeted primary care organization leaders at all Ontario family health teams, community health centres, nurse practitioner–led clinics and Aboriginal Health Access Centres. We asked questions from the Measuring Organizational Readiness for Engagement (MORE) and Public and Patient Engagement Evaluation Tool (PPEET) questionnaires. We used factor and mediation analysis to identify organizational conditions and activities that are associated with the outcomes of patient engagement, affecting board decisions, program-level decisions and the formation of collaborative partnerships.Results:We achieved a 53% response rate (n = 149/283); after removing missing data, our final sample size was 141 respondents. Most respondents perceived that their organization’s patient engagement activities and resources were insufficient. Processes that had a direct effect on outcomes (β = 0.7, p < 0.0001) included planning, training and supporting employees; identifying, recruiting and supporting relevant patients; and using leaders. Structures — including an organizational mission and vision for patient engagement, and policies, procedures, job positions, training programs and organizational culture that reflect that mission — indirectly affected outcomes, mediated by the aforementioned processes (β = 0.7, p < 0.0001).Interpretation:Based on the perceptions of primary care leaders, organizational structures and processes are related to successful patient engagement. Organizations that seek to improve patient engagement should assess their commitment and follow-through with associated resources and activities.