To test the effectiveness of the 1995 Royal College of Ophthalmologists (RCO) guidelines for screening for retinopathy of prematurity (ROP) in one regional neonatal intensive care unit, an analysis was carried out of screening examination results over a 4 year period, retrospectively applying the rules of the 1995 RCO guidelines. Four hundred and forty-eight examinations would have been performed in 258 infants, significantly fewer than the 764 examinations which had been performed using our existing screening protocol. Threshold ROP developed in 36 infants, and would have been detected promptly in every case. No case of threshold ROP developed in infants of birth weight greater than 1250 g. The 1995 RCO guidelines for ROP screening provide an effective and efficient means of detecting treatable ROP. The need to include infants of birth weight > 1250 g should be reviewed at a future date, following a period of further national data collection.