Cataract surgery with an intraocular lens implant is one of the most common and thought to be the most effective surgical procedure in any field of medicine. Although aging is the most common cause, other factors are also known to be associated with cataract formation. Although cataracts are the domain of ophthalmology, primary care physicians are frequently the ones to whom patients present with vision complaints. Knowledge of cataract symptoms, how to evaluate them, and a basic understanding of the surgery to correct cataracts make primary care physicians an integral part of treating this leading cause of preventable blindness.