According to Rein, some of the $18 billion is already accounted for: Seven billion dollars of the bill will be covered by Uncle Sam through approved changes to the federal 2016 budget that permit a larger variety of businesses (such as farms) to claim tax deductions in exchange for donating food. New tax law also increased the percentage of the donation (up to 15 percent) that can be claimed in deductions, he added. An additional $1 billion will come from community composting and recycling infrastructure funded by municipal bonds, debt, or public-private partnerships.

Six and a half billion dollars, ReFED projects, can be raised through private investment from companies (such as food service companies such as Bon Appétit Management Company (BAMCO) and Sodexo), which are already putting money into their own food waste solutions. And impact investors and philanthropic foundations have the capacity to make up the balance of the funds.

In January, the Rockerfeller Foundation announced it would contribute $130 million towards initiatives ending global food waste—the first major pledge in the philanthropic community. Vared says that she anticipates that more foundations supporting hunger, food security, and climate change initiatives will start to ramp up their funding in the next three to five years as they start to understand the connections with food waste.

“If they’re already funding hunger and food security [programs], some of those dollars can be used in smart and new ways for this issue by leveraging and expanding food recovery infrastructure,” she said. “Food waste reaches across a variety of focus areas that people in philanthropy care about, and [addressing it] can help make other areas they fund more efficient.”

The authors also point to pre-existing efforts to cut food waste such as the bill proposed last December by U.S. Representative Chellie Pingree (D-Maine), which seeks to reduce food waste in grocery stores, restaurants, schools, and farms. Restaurant and food service providers, such as BAMCO, play a key role by using software to track kitchen waste and removing trays from its buffets as a way to reduce meal portion sizes. And other partner organizations are also critical, such as the Natural Resources Defense Council (NRDC), which is planning to launch a national consumer education campaign to reduce food waste with the Ad Council next month.

In her blog post on the report, NRDC food waste expert and author of The Waste Free Kitchen Handbook Dana Gunders described ReFED’s Roadmap as “just part of the puzzle.” While specific tactics are important to pinpoint, she added, a cultural shift may be the more crucial aspect of the effort.

“If you threw a half-eaten sandwich on the street, people would look at you like you’re crazy. But if you threw it in the garbage, no one would think much about that,” said Gunders at the ReFED forum. “Our ultimate goal is to shift the paradigm around food.”