AIMS--This study aimed to evaluate both the mean time intervals between retinal disease and the development of proliferative vitreoretinopathy (PVR) and the time intervals at which recurrent PVR develops following various kinds of vitreoretinal disease and surgery. METHODS--One hundred and thirty six consecutive cases of PVR that were seen and operated on between 1991 and 1994 were evaluated retrospectively. Intervals between onset of disease and PVR or recurrent PVR were noted. Conditions leading to PVR, surgical procedures, and the final anatomical and functional results were evaluated. RESULTS--Before PVR was noted for the first time, an average of 1.06 vitreoretinal surgical procedures were performed (range 0 to 3). A mean of 1.99 surgeries were performed to control PVR or to reach an end stage where further surgery would have been unreasonable (range 0 to 5). The average (median) time interval between the onset of the retinal disease and PVR was 2.0 months (range 0.5 to 45 months). The median time intervals between surgery and recurrence for the second, third, or fourth times was also 2.0 months (range 0.5 to 34 months). CONCLUSIONS--PVR starts earliest at 2 weeks after an event and subsequently quietens down within a maximum of 45 months after treatment (median 2 months). PVR may recur more than once but the time course of the disease is likely to be the same for each recurrence.