Crain’s unveiled its annual 40 Under 40 list this week and four Brooklynites made the cut.

Donnell Baird, founder of Bloc Power

According to our report on Bloc Power last fall:

The company’s mission is to make buildings in low-income neighborhoods greener while creating jobs in those communities. That goal hits home for Baird, who grew up in Bed-Stuy. After graduating from Duke in 2003, he returned to Brooklyn to work as a community organizer in Brownsville. It struck him from the beginning that one way to address the myriad issues he saw firsthand — failing schools, high incarceration rates — was to find better jobs for the neighborhood’s residents. One thing Baird noticed: the buildings, including within public housing, were in need of repair.

Brad Hargreaves, founder of Common

Earlier this year, we named Common the No. 1 startup on the rise in our own realLIST.

Common comes out on top not just for the tremendous success it has had in such a short time (it was founded just a year and a half ago) but also because it re-envisions a fundamental part of our society: how we live together. In big cities where housing demand outstrips supply, the coliving company has created value for its residents and making the most of space, with each new project larger than the one before it.

 Viraj Puri, cofounder of Gotham Greens

Gotham Greens has two locations in Brooklyn, in Greenpoint and in Gowanus, as well as one in Queens and one in Chicago. According to Crain’s:

At a time when urban farming is often a small-scale community project, Puri has pushed Gotham Greens to succeed by turning fallow urban footage into plots that produce 20 times the expected yield. From 2015 to 2016, revenue soared 270%, and employment tripled to 150 with the opening in Jamaica and another—a 75,000-square-foot greenhouse—in Chicago. Gotham Greens has raised $30 million and this year plans to raise $50 million to fund more greenhouses.

Katelyn Gleason, cofounder of Eligible

From Crain’s:

Each month Katelyn Gleason’s company helps 14 million patients figure out whether their health insurance will cover a doctor’s visit and how much they’ll have to pay out of pocket. Eligible can help patients avoid a dreaded surprise medical bill months down the line, and yet many who benefit from the technology have never heard of the Brooklyn-based startup that’s behind it.

See the full list