ProPublica and Vox.com announced this week that they’re hiring a joint video producer: “These types of collaborations are a comfortable, natural thing for our team to do,” Vox general manager Andrew Golis told Nieman Lab. And ProPublica has won three Pulitzers for collaborative reporting it’s done — this year, with the New York Daily News; in 2016, with The Marshall Project; and in 2010, with The New York Times Magazine.

Such partnerships between nonprofits and commercial news organizations are becoming more common. At their best, they benefit both sides: The commercial publishers get expert reporting in specific areas that they don’t have time to devote resources to in their own newsrooms, while the nonprofits get extended reach for their work (and, hopefully, money, too). A report out Thursday from the American Press Institute, written by Jason Alcorn, looks at the ways in which they can be successful.

Some tidbits from the report:

— Because many nonprofits publish somewhat infrequently, they have a hard time building web followings. Some find ways to do daily reporting. For others, partnerships help them reach larger audiences. “We made a conscious decision at the outset that we weren’t going to try to build audience at our own website,” Sam Fromartz, the cofounder and editor-in-chief of the Food and Environment Reporting Network, told API.

— Just exposure, though, isn’t enough: “Successful partnerships often involve the commercial newsroom paying the nonprofit.” Jim Heaney, editor and executive director of Investigative Post, said that when his nonprofit partnered with Buffalo’s WGRZ-TV, “I made it very clear I won’t work for exposure.” This resulted in a contractual relationship:

The partnership remains the largest single source of revenue for Investigative Post, and the nonprofit has negotiated increases in its fee since the original contract was signed. Heaney wouldn’t disclose the current amount, saying only that it was between $50,000 and $100,000 a year. That would put it among the largest such arrangements identified in this research.

In Michigan, the annual budget for a partnership between Crain’s Detroit Business and the nonprofit Bridge Magazine is less than $100,000, according to Bridge publisher John Bebow. Most of that goes to the salary of a shared business reporter in the state capital, split evenly between the two organizations. Crain’s pays its half to Bridge Magazine each quarter. Bebow counts it as earned revenue in his annual budget and reports to funders.

Both are long-term, contractual relationships. Partnerships for a single story or a short-term project involve less money, of course — comparable to what a commercial publication would pay an experienced freelancer. I heard a wide range of figures in my interviews, from $100 to a few thousand dollars per story. Stories for a national market command higher rates. Newspapers typically pay the least or nothing at all, even for front-page stories.

“Some nonprofits do good journalism but don’t solve a problem faced by commercial news outlets. The commercial outlet will take the nonprofit’s stories if they’re free, but if there’s a price tag, they’ll just do without,” writes Alcorn. “In this case, it’s time to rethink whether the partnership is worthwhile.”

— Vice News pays The Marshall Project $2,000 for each weekly installment of “Life Inside,” fact-checks the stories, provides illustrations, and often writes the headlines. “No money changed hands when the column first began; it was treated as an experiment. After the series gained traction, The Marshall Project asked Vice to start paying for it.”

— It’s important to make sure everyone’s on board. “The Marshall Project experienced a rare failure when it undertook a project with a mid-sized newspaper in New England.” The partnership collapsed when “the newspaper’s leadership handed the story to an editor who hadn’t been briefed on it and wasn’t fully on board,” and “The Marshall Project assigned an editor who came out of magazines to oversee the newspaper collaboration. Her approach and editing process didn’t mesh with the newspaper’s, making it hard to work through differences.”

For help making a contract, the report includes examples that have been used by a number of nonprofits.

The full report is here.