Hello, I'm Marie Ko Ooi. Welcome to Business Daily Meets from the BBC World Service. This is where we speak to interesting people from the world of business from around the globe. Today, it's the story of Japan's richest man who's estimated to be worth more than $45 billion. I think I was just lucky.

That's Tadashi Yanai, the boss of Uniclo parent company Fast Retailing.

He took over his father's clothing business and opened his first ever Unicler store in the Japanese city of

Hiroshima 40 years ago.

I had zero interest in fashion, but it was a family business.

We live upstairs of our stores, so clothing was part of our lives.

Mr. Yanaai grew his firm from a revenue of a hundred million yen to three trillion in one generation.

To become the world's biggest fashion retailer, though, he needs to at least... million to three trillion yen in one generation.

To become the world's biggest fashion retailer, though, he needs to at least double that.

But he even has a bigger target, a revenue of 10 trillion yen.

Age 75, can he achieve that as the company's president before passing the button to his successor?

I like to achieve it and I believe I need to achieve it.

That's retail billionaire Tadashiyanai coming up on today's Business Daily Meets.

I met Tadashi Yanai at Uniclo Parents' Firms' headquarters in Tokyo.

It's a ginormous complex housing thousands of its employees.

I was taken to the firm's library where staff can borrow books that their boss has enjoyed.

This is actually the second time I interviewed him. And when we last spoke in 2009, he was opening the first ever Uniclaw store in Singapore.

The brand has been expanding rapidly since.

So I asked him if he thinks he can achieve his goals over 10 trillion yen revenue

and to be the world's biggest fashion retailer before he retires.

Yeah, well, I'd I need to achieve it.

In order to do that, we need to imagine how different a 10 trillion yen firm is from a 3 trillion yen firm,

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