How a World Cup footballer co-founded a $600M sustainable shoe brand

Executive overview

Most footwear is made from petroleum-based plastics or leather — polluting at every stage of its life. Allbirds set out to prove that natural materials could outperform synthetics while leaving a smaller footprint on the planet.

Co-founders Tim Brown (former New Zealand international footballer) and Joey Zwillinger (material scientist) combined outsider naivety with deep materials expertise to build from a Kickstarter to a globally recognised brand.

Great products come first — sustainability is the method, not the marketing.

From sport to startup

• Tim's career as a sponsored athlete exposed him to how loud and plastic-heavy mainstream footwear had become.
• A business school professor pushed him to stop theorising and put the idea into the market.
• The first material chosen was merino wool — odour-resistant, temperature-regulating, moisture-wicking, biodegradable.
• A Kickstarter launch raised $120,000 in three days — fast for any category, exceptional for fashion.

Finding a co-founder and a bigger mission

• Tim felt the Kickstarter lacked a north star; he wasn't sure he wanted to continue.
• Joey Zwillinger brought a background in green chemistry and biotechnology, and reframed the venture around climate change and material innovation.
• Joey's conviction supplied the "big dream" Tim had been missing.
• Their complementary strengths — athlete credibility and materials science — let them approach the industry without legacy assumptions.

Early obstacles and the decision to persist

• Industry experts in wool and footwear told them the opportunity was too small and consumers wouldn't care.
• The founders kept asking why it hadn't been done before — and were never satisfied with the answers.
• They trusted their own judgment while still seeking feedback selectively.
• Key lesson: not seeking feedback is naive; following all of it is worse.

Building the product and finding manufacturing

• Making shoes from novel natural materials is significantly harder than standard footwear production.
• They found a factory in Busan, South Korea aligned with their quality standards after a long search.
• Rather than launching with a wide range, they focused on a single silhouette: the Wool Runner, launched 1 March 2016.
• Time Magazine named it the most comfortable shoe in the world; $1M in sales in the first month.
• The Wool Runner has had ~40 iterative improvements since launch — innovation as refinement, not just addition.

The sustainability framework

• 20 billion pairs of shoes are made annually; nearly all use petroleum plastics or cow leather, with no circularity.
• Allbirds labels the carbon footprint on every product — on the tongue or heel — the same way calories appear on food packaging.
• The logic: measure first, then reduce to zero, then work backwards to allocate resources.
• Materials portfolio now includes merino wool, eucalyptus fibre, and sugarcane-derived soles.
• The principle: customers buy great products, not sustainable ones — performance and comfort are non-negotiable.

Operating principles for a small challenger brand

• Purpose anchors every decision — the company makes great products; truly great products are sustainable.
• Prioritisation is the second pillar: say no 99 times for every yes; saying yes to three things instead of one is where focus erodes.
• Allbirds is still a low-millions unit seller in a 20-billion-pair industry — the runway is vast if focus holds.
• Long time horizons matter: a full year was spent training factories and developing materials before launch.

Lessons from sport applied to entrepreneurship

• Athletes learn to trust compounding improvement that isn't visible day-to-day.
• Building a business requires the same tolerance for slow, invisible progress.
• Surrounding yourself with people smarter than you, working on a problem bigger than any individual — that is when work is at its best.
• The privilege of entrepreneurship: you choose the problem, you choose the team.