Nearly 30 percent of the adult population in the country has had at least one dose of a coronavirus vaccine. By now, you probably know quite a few people who’ve been vaccinated.

But actually getting shots into arms is not easy. And it’s not going to get any easier. At some point, the U.S. is going to run out of people eager to get the vaccine, and we’ll need to work hard to convert those who are still hesitant or don’t know how to get it. It won’t be the first time we’ve done so, of course. For months now community leaders have been working to overcome transportation challenges, language barriers and digital divides.

To better understand the challenges to come, we talked to five people who’ve been struggling with these issues since the first vaccines became available. They’ve been obsessed with the questions of conversion and access. How do you get the shot to people who aren’t going out of their way to get it?

Each leader had their own answer to that question. But one overarching theme emerged: It’s about meeting people where they are.

Listen to the podcast or read the transcript on vaccinating hesitant americans by Anna Rothschild at FiveThirtyEight.