More than 50 years ago today, an American volunteer program was launched by the U.S. government to promote cross-cultural exchange.

Today that idea has inspired more than 200,000 Americans to work in 139 different countries, together with governments, schools, NGOs, entrepreneurs and other groups on issues as varied as HIV/AIDs, technology and environmental preservation.

Former President John F. Kennedy first articulated what the Peace Corps should be in an improvised campaign speech while standing on the steps at the University of Michigan in 1960.

"How many of you who are going to be doctors, are willing to spend your days in Ghana? Technicians or engineers, how many of you are willing to work in the Foreign Service and spend your lives traveling around the world? ... I think Americans are willing to contribute. But the effort must be far greater than we have ever made in the past."

President John F. Kennedy. (Associated Press)

There have since been many notable Peace Corps volunteers, including travel writer Peter Hessler, Sen. Chris Dodd (Conn.), Netflix founder and CEO Reed Hastings, Post reporter Al Kamen, several U.S. ambassadors and many, many founders or directors of nonprofit organizations.

A Peace Corps video postcards page chronicles the experiences of many recent volunteers in the program.

Were you a Peace Corps volunteer? Tell us about your experience.