Charles Best started DonorsChoose.org at the age of 24 out of his Bronx, N.Y., classroom. The website connects donors directly to classrooms in need: You give to a particular project—$20 for art supplies, for example—and get back photos and personal thank-you notes so you can see how students use your gift. The model is so touching and inspiring, it’s a wonder it has succeeded.

According to recent research, people tend to perceive organizations as being either warm or competent, not both—and they are much more likely to do business with the competent one. This is unfortunate for nonprofits, especially those that have services or wares to sell. Mozilla, the hybrid (nonprofit and for-profit) software organization that supports the Firefox web browser, makes a messenger bag. Researchers manipulated the site from which the bag was sold and asked consumers what they thought of Mozilla. “The same company framed as a dot-org is seen as warm and inspirational and significantly less competent and effective than its dot-com arm, which is seen as competent and effective but not warm or inspired,” says Jennifer Aaker, professor of marketing at the Stanford Graduate School of Business.

When Aaker and colleagues tried to sell participants a laptop bag from the eco-friendly marketplace World of Good, the potential buyers were less willing to turn their money over to the dot-org branch of the organization than to the dot-com one. This pattern reversed when participants saw a favorable review of the nonprofit organization from The Wall Street Journal (although not from the Detroit Free Press).

The trick, then, is to be seen as both warm and competent. “The companies that are cultivating both perceptions are the companies that are winning right now with Millennials and with social media,” says Aaker. Highstatus partnerships help increase perceptions of competence, as does being seen as data driven.

Over at DonorsChoose.org, endorsements from The Wall Street Journal, NPR, and CNN adorn the home page. The nonprofit also measures and posts its impact daily in hard statistics—on dollars raised, students reached, and economic need, as well as by subject, grade, and resource. After 10 years, DonorsChoose.org has raised more than $72 million in donations and helped more than 4 million students. Best seems to have found that ideal combination of warmth and competence.

“In general, the perception has always been that by being a nonprofit, there must be some ‘nons’: They’re not as capable or not as good,” says Robert Ottenhoff, president and CEO of GuideStar, which makes data on the efficiency and effectiveness of individual nonprofits available to the public. “Increasingly, I think that’s going to be the kind of question that nonprofits are going to have to answer: Yes, we’re capable. Yes, we have the capacity to do this. Yes, we can make a difference.”

Jennifer Aaker, Kathleen D. Vohs, and Cassie Mogliner, “Nonprofits Are Seen as Warm and For-Profits as Competent: Firm Stereotypes Matter,” Journal of Consumer Research, 37, 2010.

Read more stories by Jessica Ruvinsky.