Writing good referral letters is more of an art than a science. The letter needs to convey clinical information in a way that is effective and serves the best interests of our patients, but must not offend or patronise the recipient. In the course of their professional practice, optometrists will write referral letters to a number of different healthcare professionals who are also involved in the care of their patients. These healthcare professionals include the obvious ones, such as general practitioners (GPs) or local ophthalmologists, but there are also less obvious professionals who may be involved, such as a local diabetic nurse.