The 2008 TIME 100

When Nancy Brinker, 61, meets up with her sister Susan G. Komen on the other side of the pearly gates, she will be able to say, "I did what you asked." The foundation Nancy established after her sister died of breast cancer in her mid-30s has become a household name around the globe.

It was more than 25 years ago that Nancy accompanied her big sister on the odyssey that follows a breast-cancer diagnosis. Before she died, Susan begged her can-do little sib to help the half a million women worldwide who are diagnosed with breast cancer every year. Not long after, Nancy organized women in Dallas to "Race for the Cure" for breast cancer. Now more than a million people all over the world run to support research and community health—raising almost $1 billion over the past quarter-century.

After being named ambassador to Hungary in 2001, Nancy brought breast-cancer awareness to a wider world, and now, as White House chief of protocol, she has enlisted the ambassadors to a dozen countries to race in recognition of the needs of local women.

What a difference she has made! Research grants dispensed by Susan G. Komen for the Cure have contributed to new treatments that have led to a marked decrease in the mortality rate. Along with millions of other breast-cancer survivors, I'm grateful to Nancy Brinker. She's done her sister proud.

Roberts is a news analyst for NPR and a veteran reporter for ABC