Silicone oil was introduced into ophthalmic surgery by Paul Cibis in the early 1960's in an attempt to treat giant retinal tears and cases where retinal detachment had failed to respond to conventional scleral buckling tech niques. His understanding of the nature of vitreous pathology and how it related to complex retinal detachment laid the foundation for modern vit reoretinal surgery. Cibis's success with these problems together with his rationale for sepa rating membranes from the retina led others to try their hand at learning his techniques. At the same time much criticism was levelled at the concept of injecting what was regarded as a foreign material into the eye, as well as to the whole idea of operating within the vitreous cavity. Some of this was personal, some due to a lack of understanding of the underlying pathology and some due to disappointment following surgical failure us ing the new methods. Early results were certainly encouraging but it was not until the advent of pars plana vitrectomy that it became possible to develop more refined methods in combination with the use silicone oil so that much better results could be obtained.