Background:  Allbirds is a New Zealand-American (what a combo) footwear and apparel company worth a massive $1.9 billion. It's really famous for its comfy Wool Runner - a sneaker made of NZ Merino Wool. Ashton Kutcher, Ben Affleck, Hillary Duff and even Matthew McConaughey are all big fans. 

What happened: But on top of being really comfy, Allbirds prides itself on being as eco-friendly as possible. Its supply chain has been carbon-neutral since 2019, and its sneakers have 30% less carbon footprint than the average pair. 

What else: Allbirds has just filed for an IPO, and they've described it as the "first sustainable public equity offering". But they're also currently facing a class-action lawsuit for making misleading sustainability claims. So are they really that sustainable? 

So what's the key learning?

The circular supply chain is a model that encourages manufacturers, like Allbirds, to take old materials and convert them back into raw materials - and then re-make them into products for resale. 

A circular supply chain is great for the environment, because there ends up being less waste. And, it's good for companies too, because it costs less to recycle materials than it does to buy new ones. 

Nike's Reuse-A-Shoe program encourages shoppers to recycle their old shoes at local Nike sellers. Adidas' Parley for the Oceans partnership sees the company make sneakers out of recycled plastics for the oceans. And a circular supply chain could be just what Allbirds needs to walk the walk. 

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