Like a growing number of her peers, architect Stephanie Horowitz believes in the design community’s inherent responsibility to address climate issues. So much so that her firm works only with clients who want to build or retrofit buildings that aim for net-zero energy use.

“When we meet with potential clients, it’s a vetting process,” says Horowitz, managing director of ZeroEnergy Design in Boston. “We’re very clear that this is the way that we practice architecture—it’s not negotiable.” Sustainability-centric details such as flashing, insulation, air sealing, and decarbonization are presented on equal par with floor plans and cladding. “The way that all of these things are considered is part of the design service,” she says. “It just kind of comes with the package.”

Mette Aamodt, principal of Aamodt/Plumb Architects in Cambridge, Massachusetts, takes a similar approach. Most clients are drawn to her firm’s mission-driven work. “For others, we try to educate them and be upfront about it. Sometimes we’re going to convince people; sometimes we’re not,” she admits, “but the onus is on us to make the case.” Aamodt focuses on quality over quantity and designs built with clean, healthy materials and fair labor.

For professionals like these, business as usual is simply outdated. In the U.S. today, buildings consume 39 percent of total energy used—higher than both the transportation (29 percent) and industrial (32 percent) sectors. But what if buildings—or even entire cities—could generate more energy than they used, clean the surrounding air and water, and even sequester carbon dioxide? The idea isn’t too far-fetched.

Technology to mitigate emissions already exists, is accessible, and can even be cost-effective. And small course corrections in our approach to the built environment could make a big a difference in emissions industry-wide. (Designing for resilience—that is, creating and protecting built environments that will withstand rising seas, more frequent and severe storms, and other effects of climate change—is also paramount.) According to Paul Hawken’s 2017 book Drawdown, if just 9.7 percent of new buildings were net-zero energy by 2050, global greenhouse gas emissions would be 7.1 gigatons lower. That’s equivalent to eliminating annual emissions from all livestock worldwide. Yet the biggest barrier to building greener buildings and cities may not be cost or political will, but simply inertia.