To review the rationale for various methods of perioperative prophylaxis in elective cataract surgery. The surgical and ophthalmologic literature is reviewed to determine accepted principles for the use of perioperative prophylactic agents in clean elective surgical procedures. After an assessment of the nonophthalmic surgical literature, specific principles are applied to the use of antimicrobial agents in perioperative prophylaxis of cataract surgery. Current practice patterns and specific techniques of perioperative prophylaxis are scrutinized. The emerging problem of antimicrobial resistance in the world and specifically in ophthalmology is addressed. Recommendations are offered balancing the needs of the individual patient with the best interests of society as a whole. Potent therapeutic agents should be reserved for therapy. A method of perioperative prophylaxis is suggested, with a stratified approach indicated in selected circumstances. A clear consensus is probably not possible with divergent views expressed.