What does the Peace Corps leave behind? Schools are built. Wells are dug. Crops improve. Communities grow stronger. But perhaps the Peace Corps' greatest legacy isn't what it builds overseas. It's the people it changes.

Young Americans leave home hoping to change another country. They return with their eyes opened to a world of new possibilities. The lessons they bring home often shape a lifetime of service.

Few lives illustrate that transformation better than Sam Farr's.

Before he became "Mr. Peace Corps" and spent forty-two years in public service, Sam was simply a 22-year-old searching for his place in the world.

His first attempt to join the Peace Corps ended before it began. After months of training in 1963, he was deselected. No explanation. No second chance.

Most people would have walked away. But Sam's mother, who was battling cancer, gave him advice that quietly changed the course of his life: "In America, you can always appeal a decision you don't like."

So he appealed. He studied Spanish, reapplied, and accepted an assignment to Medellín, Colombia.   She was right about the appeal. She was also right to send him—knowing it would likely be the last time they would see one another.

Like many new Peace Corps Volunteers, Sam arrived believing he had come to teach. Instead, he discovered he had come to learn. The people of his barrio became his teachers.

Together they built a soccer field on a lot strewn with boulders too large to move. But his neighbors had an idea: wrap the rocks in old inner tubes, burn them overnight, then cool them with water until they cracked apart. "Third World dynamite," as Sam calls it.

Then they built a one-room school, making adobe bricks one at a time with a hand-operated CINVA-RAM. Everyone helped—even the children, who loved pulling the heavy lever that compressed each brick. Sam secured the equipment and worked alongside his neighbors, but the community built the school.

It was designed for thirty students. On opening day, one hundred children arrived. They hadn't come because an American had built a school. They came because their community had.

That lesson stayed with Sam for the rest of his life. Community development wasn't something you did for people. It was something people did for themselves when someone listened, earned their trust, removed barriers, and believed in their ability to succeed.

The community's next challenge was sanitation. Residents agreed to dig the drainage ditches themselves if the city would provide the materials.  Sam connected barrio leaders with city officials. The people supplied the labor. The city supplied the infrastructure. Together, they made progress.

It was another lesson Sam would carry home: government works best not when it acts for people, but when it works with them.

"My goal," Sam says, "was to work myself out of a job."

Then tragedy struck.

While Sam was serving in Colombia, his mother lost her battle with cancer. Not long afterward, his father and younger sister, Nancy came to visit him. During that visit, she suffered a devastating fall from a horse and sustained a severe head injury.

In the United States, a neurosurgeon would likely have been minutes away. In Colombia, hours passed before a specialist could be located and flown in. Nancy died.

Years later, Sam reflected on what that experience taught him.

"Living in poverty, I always knew I could escape. As an American with a passport, I could leave. None of my neighbors had that option."

Then, when his sister died in a poor rural hospital, he understood something even deeper.

"I realized there is no escape from the effects of poverty. Only what-ifs."

He later recalled, "I said, you know what? This is what I'm doing. I'm going to work to make sure that no child, no family has to suffer the pain and agony that I had just suffered."

That promise became the compass for the rest of his life.