Practices of 300 randomly selected primary care physicians in Ontario and, through their physicians, 10 patients over age 65 with known DM in each practice will be recruited to participate. Practices (physicians and their index patients) will be randomized to one of 3 arms: 1) physician intervention, 2) patient intervention or 3) control. In arm 1, participating physicians will receive confidential prescribing feedback on the ABCs and, as a masking intervention, patients will receive educational materials regarding DM eye care. In arm 2, patients will receive a mailed educational intervention regarding blood pressure and lipid control while physicians will receive education and feedback regarding eye care as a masking intervention. In arm 3, no educational intervention regarding hypertension and lipids will be provided and both patients and physicians will receive the eye care intervention. Data sources will be claims data from the Ontario Drug Benefit Program and the Ontario Health Insurance Plan and the Ontario Diabetes Database (a validated, linkable administrative data diabetes registry).