The 2010 TIME 100

In less time than it takes to read this magazine, a simple surgery can give a blind person her eyesight back.

A miracle? Absolutely. But Dr. Perumalsamy Namperumalsamy, 70, and his army of cataract fixers at India's Aravind Eye Care Hospitals make it look easy. The surgery has been around for decades, but the chairman of Aravind — which was founded in 1976 with the goal of bringing assembly-line efficiency to health care — figured out how to replace cataracts safely and quickly: 3.6 million surgeries to date, a new one every 15 minutes.

Equally brilliant is the business model: the 30% of patients who can afford to pay subsidize free or low-cost care for the 70% who are poor. "All people have a right to sight," Namperumalsamy says. As I write these words after a long day spent in the slums in India, I cannot tell you how much admiration I have for him and his team.

Mullaney is a co-founder of the Smile Train, which provides more than 125,000 free cleft surgeries per year for kids in developing countries

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