The labor movement, especially over the past three decades, has faced many setbacks, but Mr. Rolf said he saw no option but to keep fighting.

“It was not our choice to be born at this time when the American dream is at its greatest level of risk,” he said. “But it will absolutely be our fault if we don’t do something about this.”

How We Picked Our Visionaries

People love lists.

We want to check out the best places to travel, catch up with the best inventions of the last 100 years, be in the know about the best-dressed people, the best books, the best schools. And on and on.

Of course, there is a risk to listmaking. Maybe your choices won’t hold up over the years. Maybe the best book of decades ago seems not so great today.

With the listmaking fervor and its risks in mind, we searched for people who would fit our criteria for visionaries. They had to be people who are forward-looking, working on exciting projects, helping others or taking a new direction. We wanted diversity in gender, race and ethnic background.

We assigned writers who are knowledgeable about the subjects we deemed most important. And we limited the list to 30.