Ira Glass used to worry This American Life would never be as strong as it was in its first few years on the air. But almost 18 years later, the founder and host of the weekly radio documentary program insists the show has never been better. And he says that contrary to what people may think about radio journalism, TAL is thriving as a business, thanks in no small part to an expanding digital and podcast audience.

Glass recently sat for an interview with Slate’s Jacob Weisberg and discussed, among other things, why he and his team abandoned a foray into television and how that has helped them focus on what they do best.

You can watch Part 1 of our Glass interview, which focuses on the art of the interview.  In the second segment, Glass reflects on a major milestone: the upcoming 500^th episode of TAL. And in the third part, he talks about what he believes is the essence of his show and how his parents helped bring that out.