In ten cases of retrolental fibroplasia no significant relationship could be found between the stage of the disease and the neonatological values. The treatment given - laser coagulation, subconjunctival cortisone injections (glaucoma, complicated cataract) and pars plana vitrectomy - triggered different reactions in the eyes. Laser coagulation interrupted the process but fresh proliferation occurred; pars plana vitrectomies were followed by rapid efflorescences of the proliferations: Only in two of eight cases in stage V was vision permitting orientation achieved, with strikingly good close-range vision in one case. The considerable efforts involved and the mental strain on parents, patients and physicians are discussed in the light of the low rate of surgical success. A positive result can only be achieved if certain prophylactic rules are observed.