As epidemiological evidence demonstrating the effectiveness of primary prevention interventions accumulates, it is becoming apparent that there is substantial evidence-to-action gap and bridging this gap requires understanding whether public health systems have adequate capacity to develop and implement effective, evidence-based policy solutions. Because of ongoing evolution in the structure, organization, funding, legal mandates and mission of organizations within Canada’s public health system, continued monitoring of organizational capacity for chronic disease prevention is critical. The Public Health ORganizational CApacity STudy (PHORCAST) is the first longitudinal investigation of organization capacity for chronic disease prevention in Canada. Cycle 1 was conducted in 2005 and included all 258 organizations with formal or informal mandates for chronic disease prevention in Canada (92% response). Cycle 2 was completed in 2010 and included 239 organizations (90% response). Cycle 3 (conducted in 2022 10-15 years after the original two PHORCAST cycles) covers changes in organizational capacity in these organizations related to the COVID-19 pandemic. To date, PHORCAST has provided new knowledge on the infrastructure of the preventive health systems in Canada. It has helped monitor changes in organization capacity over time, identified provincial disparities in organizational capacity, and highlighted areas needing improvement.