Generally, doctors perform cataract surgery on one eye at a time. This enables the surgeon to thoroughly assess the surgical outcome and, if needed, make adjustments before treating the other eye. There is also a precautionary aspect to this approach, as Cataract surgery is not without risk. There is a slight chance of infection or other complications. Treating only one eye at a time, these risks are easier to manage. Finally, having cataracts in one eye doesn't mean you have them in both. The condition is not "contagious" from one eye to the other. Therefore, you may be ready to correct vision in one eye long before the other eye may develop cataracts significant enough to warrant removal.