The 2010 TIME 100

Courageous and purposeful, Sister Carol Keehan, 66, is a deeply religious Catholic woman dedicated to carrying out the healing ministry of Jesus Christ on earth. Her leadership of the Catholic Health Association of the United States (CHA) has been defined by advocacy for the poor and an unwavering respect for human dignity. Her fight to reform health care was an extension of her concern for the most vulnerable in our society and was as integral to the mission of CHA as providing medical services. Undeterred by her critics, she refused to back down as she fought for reforms that would include prenatal and maternity care and coverage for uninsured children. She fought for those who couldn't fight for themselves.

Leadership is not about doing what's easy. It's about doing what's right. Last March, my husband, Senator Edward Kennedy, said he looked forward to being a foot soldier in the fight for reform and vowed that, this time, we would not fail. Sister Carol was a vital foot soldier in that fight.

And this time, we did not fail.

Kennedy is an advocate, a lawyer and the widow of Senator Edward Kennedy

TIME 100 Social-Networking Index: 0

Correction appended: April 30, 2010. The original version of this article misidentified Keehan's age as 63. She is 66.