A case-control study of idiopathic, rhegmatogenous retinal detachment (IRD) was conducted to investigate potential risk factors for developing IRD. These included some factors reported previously, such as cardiovascular disease, and some not under suspicion, such as cigarette smoking and iris colour. Cases (n = 198) were incident cases of IRD who were hospitalized for surgical repair of their detachments. Controls (n = 655) were patients hospitalized for conditions unrelated to suspected risk factors for IRD. The risk of IRD appeared to increase with increasing age, and the relative risk for self-reported myopes, compared with non-myopes, was elevated (RR = 3.4, 95% CI = 2.3 - 5.0). The relative risk of IRD was decreased in current smokers (RR = 0.5, 95% CI = 0.3 - 0.8); although there was not a significant trend of decreasing relative risk with increasing amount smoked, the estimate was lowest in those who smoked most heavily. Risk did not appear to be related to gender, eye colour, history of myocardial infarction, or history of hypertension.