alexandra_kentPurpose Prizes have been called "genius grants" for people over 60 and are awarded every year to social entrepreneurs who devote their encore careers to making the world a better place.

The application deadline for the 2012 prizes is March 30. Five winners will each receive $100,000 to continue their enterprises.

In the six years since Civic Ventures created the awards, the San Francisco nonprofit has given away more than $3 million to more than 30 winners. Among those honored: a psychiatrist who started a national counseling network for traumatized veterans, the former head of a business incubator who helps Detroit startups and a filmmaker who created a foundation to aid children in China's orphanages.

I recently caught up with Purpose Prize director Alexandra Céspedes Kent to find out more about the application process and what judges look for in winners.

SA: What inspired Civic Ventures to create the Purpose Prize?
AK: We created the Purpose Prize the first year that boomers started turning 60. We knew millions of older adults were working longer, out of desire and increasingly out of need. We wanted to highlight people solving major social problems in their encore careers, a new stage of work that combines personal meaning, social impact and the opportunity for continued income. We do that by investing $100,000 in each winner and promoting their accomplishments.

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SA: What types of achievements are judges looking for in winners?
AK: Judges look for people who prove that innovation and creativity have no age limit. We look for people who are using their experience and skills in a new way, from a former lighting director on movie sets who invented a peanut-sheller to revolutionize rural farming to a food distributor who quit his job to help food banks devise new ways to provide farm-fresh produce to the needy.

SA: Do you need to start an organization, or can you be recognized for something else?
AK: Some winners were hired into their positions. Others founded new organizations. Most earn a modest living, and others work for free because they may not need the income. What they all have in common is that they decided to embark on a new path in the second half of life, one marked by a significant body of work in service to the greater good.

SA: Do you need to work for a cause for a long time, and if so, how long?
AK: We like to say we're the opposite of a lifetime achievement award. We consider candidates who have shifted gears in the past 15 years, devised a working solution to a big problem and who can show that there's more to come.

[Related: 5 Social Entrepreneurs Changing the World]

SA: What's the best way for an applicant to present accomplishments?
AK: Tell your personal story. What compelled you to redirect your experience and talents? What makes you passionate about the issue at hand? What have you accomplished, and what do you still want to do? We love stories. We also love hearing data about a candidate's impact.

SA: Over the years, how many people have applied?
AK: We've received over 7,000 nominations and self-nominations since the Purpose Prize began in 2006.

SA: What happens if you apply or are nominated but don't win?
AK: All nominees who don't win can reapply or be renominated the next year. We take care to let every applicant know that they are trailblazers in a larger movement of adults who are redefining aging and remaking America in their encore careers.

SA: What's your best advice for someone thinking about applying for this year's prize?
AK: Before drafting a nomination or self-nomination, take time to think about your own life transition. Why did you start your encore career? Some people restarted after a crisis; others had a desire to move from success to significance; still others might cite a realization that no one else was addressing a community problem. Tell us what sparked you into action.

Related: Purpose Prizes Honor Innovators

SA: Any parting thoughts?
AK: Purpose Prize winners are an inspiration to older adults who are thinking of what's next in the second half of life. Read their stories or nominate someone you know for the 2012 Purpose Prize at www.encore.org.

Apply for a 2012 Purpose Prize or nominate someone here.