James Otieno is fulfilling his dream of building schools in Kenya in his encore career. Photo by BusinessWeek.

In a Special Report called “The Case Against Retirement,” BusinessWeek proclaims that changing demographics and financial reality are propelling a tectonic shift in which Americans work longer in encore careers. While BusinessWeek defines encore careers more broadly than we do, including jobs like flying airplanes and raising llamas, the publication does spotlight some experienced individuals who are advancing social change.

Among them is James Otieno, 49, who took an early retirement package from HP in 2007, then became an Encore Fellow working at the Silicon Valley Education Foundation through a pilot project with Civic Ventures. Now he’s building schools in his native Kenya, as well as Sudan, through a foundation he started.

Another is Marion Somers, 69, who grew frustrated by her inability to help more people in the geriatric-care field. After she traveled the nation, talking to people about their care-giving experiences, she started an elder-care clearinghouse with videos, blogs and other resources.

Other articles and videos explain how to determine your future path, how to find encore career and why it’s important to have a financial plan. In “Moving Beyond Do-It-Yourself Transitions to Encore Careers,” Marc Freedman, founder of Civic Ventures, recommends a range of social institutions and policy changes to make it easier for experienced individuals to find work that matters.

He describes the sector-switching obstacles that many Americans face when they choose to deviate from the well-marked path toward the “Leisure World” concept of retirement that “the mad men of marketing” have promoted for decades. What’s needed, he argues, is not just an attitude shift, but also a whole range of social institutions to make it easier for people to transition to purposeful, paid work after they finish their midyear careers.

Other articles and videos in the Special Report include:

Chris Farrell describes the financial and demographic developments that are prompting more Americans to work longer.

Karen McCormack offers advice from experts on how to create a roadmap for your encore stage of life.

Marci Alboher, the former New York Times columnist who is now a senior fellow at Civic Ventures, recommends volunteering or tapping your social network to find new career opportunities. (Video)

Lynne Ford, head of retail retirement for Wells Fargo, explains why it’s important to have a financial plan. (Video)

Access all articles and videos in BusinessWeek’s Special Report.