Global attempts to move to a 1.5° pathway rely on our collective ability to scale up new green businesses—and to do so quickly. What exactly will it take to make this happen? The imperatives are to hyperscale, how to reduce the cost of clean technology, and how to secure necessary talent and establish an operating model for ultrafast scaling. Capital expenditures will have to reach historic levels, topping $276 trillion across areas including transport, power, and buildings—an opportunity the size of which has not been seen since World War II. Given this reality, our conversations suggest the need for a new formula for building green businesses. Forces are converging to create a net-zero agenda that’s reminiscent of the execution speeds of the digital economy. While the scaling of sustainable technologies has historically stretched over many careful years, we’re now in a moment that calls for the hyperscaling of technologies. This community needs to build not just unicorns but decacorns (unicorn companies worth at least $10 billion)—and a lot of them. The McKinsey Net-Zero Transition team suggests that we would like to see 200 to 300 green decacorns by 2030.