By 2040, the American economy will be “scarcely recognizable,” according to a new report published by the Roosevelt Institute and the Kauffman Foundation.

We’ve seen glimpses of the looming changes already: freelancers now make up 34%–that’s 53 million people–of the U.S. workforce, according to a 2014 survey by Edelman Berland. In the next 25 years, this shift will accelerate in a major way towards entrepreneurship, independent contracting, and “peer-to-peer” work on platforms like TaskRabbit. Additionally, there will be major diversification of entrepreneurship as new platforms like crowdfunding and relocalized production become increasingly popular.

As traditional jobs wane, there will be some growing pains. “It’s going to put major strains on our public fiscal system,” says Dane Stangler, vice president of research and policy at the Kauffman Foundation. “We’ve built all of our massive entitlement programs–whether it’s social security for retirement or health care systems or unemployment insurance or whatever–around this notion of a fixed job.”

As we veer from this traditional work model, Stangler says the government will end up losing major payroll taxes, and that’s going to create challenges for our fiscal system unless some “very significant policy adaptations” are made.

He warns: “There’s a whole ripple effect if this is going to be an actual and growing part of the economy.”

The report, which includes insights from 30 economists, technologists, policy makers, and entrepreneurs, focuses on four main topics: the future of work, the future of technology, the future of entrepreneurship, and the future of inequality. Below are five changes to expect from America’s next economy: