Aim: To describe and improve the quality of diabetes care in general practice. Setting: General practices in Ribe County, Denmark Design and methods: A medical two pass multipractice audit circle including feedback and continuing medical education following the principles of the Audit Project Odense (APO) method. The intervention was aimed at improving the delivery of diabetes care in general practice, with focus on performance of clinical measurements, laboratory tests and referral of patients with diabetes to treatment and control by specialists. Results: Delivery of diabetes care in general practice has not always met standards of care and variation between general practitioners is wide. Completion of the APO circle significantly increased the relative frequency of HbA_1C testing from 52% to 67%, albumine-to-creatinine ratio testing from 6% to 15% and the use of microalbumin dipstick from 6% to 17% per general practitioner. Referral of patients to treatment and control by ophthalmologists, endocrinologists in diabetes outpatient clinics or chiropodists was significantly increased from 48% to 56%, from 2% to 11% and from 5% to 24%, respectively. Conclusion: Performance of diabetes care in general practice is highly variable and leaves room for quality improvement. Standards of diabetes care can be improved by a combination of audit, feedback and prolonged medical education following the principles of the Audit Project Odense (APO) method.