Those who share a birthday with Napster—which launched June 1, 1999—are turning 17 today. It’s an age when music often means the world. How differently, though, are these digital natives hearing their favorite artists compared to listeners from decades past? There’s always a risk of exaggerating the changes facing younger generations, but the shift undergone in this millennium feels less ephemeral and more profound than, say, transitioning from cassettes to CDs. This is because music is now free.

Before Napster, to hear whatever you wanted, whenever you wanted, you had to pay for it. Pirated music still exists, of course, but the real breakthrough for the music industry over the last decade has been free, ad-supported streaming. Vast libraries of songs ready at a click’s notice? Personally customized online radio stations? It’s all there, all the time—on car trips, in the shower, while sleeping or partying or working out or studying—and it doesn’t have an obvious cost.

Stone Mills, a 21-year-old musician at The Evergreen State College in Olympia, Washington, tells me that although he prefers playing vinyl or tapes, almost of all his current listening happens via YouTube. “Nowadays, my expectation of finding music on the internet for free is so high that I feel slightly offended when I can’t do it,” he says. “It’s kind of a warped mindset, actually.” It’s also, no doubt, a common one.

For all the debates about the paucity of payouts to music makers, with ad-supported streaming—unlike with piracy—at least those payouts exist. But now, the industry may be rewriting its compact with free streamers. Streaming services appear to be approaching a point of rebalancing as they try to maximize advertising revenues from the many who don't pony up for monthly subscriptions while at the same time finding new reasons for potential customers to pull out their credit cards.

Glimmers of what this realignment could mean for artists and listeners are already becoming evident. People who make music may eventually start to see their payouts from free streaming rise as services spread and advertisers follow—though it’s hard to see how those amounts will ever compare with the sales of old. People who listen to music, meanwhile, may want to get used to not being able to hear every major new release (legally) without paying for the privilege.

The problem, as Tim Westergren, founder and CEO of web-radio giant Pandora, tells me, is locating the right middle ground, where there’s enough free music to encourage paid subscriptions but not enough to condition audiences to stop paying altogether. “We’re heading into a period of reckoning, where the industry is going to make some decisions about what really makes sense,” he says. “It can’t go on as it is.”