Diabetic retinopathy remains the most common cause of blindness in people of working age but the provision of high quality eye screening for diabetic patients is still erratic in many health districts in the UK. National consensus guidelines recommend comprehensive population coverage, high sensitivity (>80%), high specificity (>95%), agreed clinical criteria, referral procedures and centralized data collection to facilitate audit. This study looks at the effectiveness of implementing a prompted recall programme for retinal screening in an inner-city district of North London. The scheme uses trained, accredited optometrists to screen patients with diabetes who are looked after in the community by their general practitioner. During the first 17 months of the scheme, 63 optometrists attended training and gained accreditation. Of the 666 patients recruited, 645 were scheduled for screening and 536 (83%) attended. Fourteen per cent of patients screened were found to have background retinopathy and 2.3% sight-threatening eye disease. In two audits, carried out 15 months apart in a random sample of GP practices, the incidence of recorded dilated fundoscopy increased from 48% at baseline to 56%, an increase of 8% (95% CIs 2%-14%). For referable eye disease, the sensitivity of this screening technique was 100%, the specificity 94% (95% CIs 90%-98%), the positive predictive value 79% (95% CIs 72%-86%) and the negative predictive value 100%. The administrative cost per case screened was Pound Sterling 12.60 (excluding clinical costs and any additional optometry payment).