Hello, welcome to Money Talks from Slate Money.

I'm Felix Salmon of Bloomberg and this is the show where we talk to the most interesting people in the world, about the most interesting subjects in the world.

And this week, I am reunited with my former colleague, Mariana Van Selle.

Mariana, welcome.

Thank you, Felix. I'm happy to be here.

Marianna, tell us, who are you? What do you do? And most importantly, what is your podcast?

I have been covering black markets for about 20 years now.

I have a show on National Geographic called Trafficked with Mariana Van Zeller,

and I recently launched a podcast called The Hidden Third.

It's called The Hidden Third because it's estimated 35% of the global economy are black and gray markets,

and yet we know very little about them.

I love this so much. So we are going to dive into exactly that. We're going to try and work out what is a black market, what are the incentives, what is the same as a normal market, where do

things go very, very different? You've been covering this, as you say, for decades now, so you

are the expert on this. And there aren't that many experts on this. So I'm very excited about

this. It's all coming up on Money Talks.

Marianna, let's start at the top. The Hidden Third.

Speaking for myself, I don't think that one third of my annual expenditure goes on black or gray anything.

I'd be surprised if it was one hundredth.

So maybe I'm just uncommonly law-abiding.

But like, tell me if it's a third of the global

economy, then that means that for everyone like me who just spends on like legal things,

there's someone else who's almost entirely spending on illegal stuff. Is that right?

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