The roomful of entrepreneurs watched in anticipation as the first participant took the stage. They’d all been in that position before: teeing up the PowerPoint slide show, fumbling around with the presentation remote and clearing their throats before launching into a business pitch.

Only this time, the ones doing the pitching were executives from large companies such as Comcast, Samsung and Time Inc.

At SwitchPitch, a tech event that connects start-up owners and big companies across the country, the roles are reversed. Executives outline specific problems they’re trying to solve and look to entrepreneurs for ideas. Now in its third year, the event returned to Washington this week to coincide with a White House event promoting diversity in entrepreneurship.

This time, the organization teamed up with the federal government, said Michael Goldstein, founder of SwitchPitch and a serial entrepreneur.

The venue for Monday’s event was the Commerce Department library in Washington’s Herbert C. Hoover Federal Building. Commerce Secretary Penny Pritzker delivered a keynote speech highlighting the department’s initiatives to promote business and called on the private sector to encourage America’s entrepreneurs, echoing the theme behind the White House’s recent measures to promote women and minority business owners.

“Collaborating with start-ups is not a replacement for companies performing their own research and development; but it is another path for a big business to develop a new product and uncover creative solutions to complex challenges,” Pritzker said. “For start-ups, collaboration is an opportunity as well – to demonstrate innovative concepts and to attract capital.”

Samsung was looking for ways to make its core phone apps more accessible to users with disabilities. Comcast wanted ideas to improve its customer experience (which attracted more than a few snickers from the audience). Time Inc. sought a more efficient system to catalogue photos from its publications, and the American Cancer Society wanted a mobile app to help consult cancer patients. (The Washington Post has also attended the event in the past).

Start-ups attending the event apply for SwitchPitch online and go through a vetting process before they are accepted. Those present included a Phoenix-based medical imaging company and the founder of a co-working space in Austin.

As the afternoon sunlight streamed in through the library windows, participants and company executives gathered at wooden tables to begin speed-dating-style meetings. It was now the start-up owner’s turn to offer solutions for the company’s problem.

Pritzker, who walked around observing the meetings, said the event was not only a good networking opportunity, but also a chance for start-ups to pick up valuable tips.

“You got to see big companies interested in the technology, but also coaching these young companies on how to be more viable,” she said.

Not every SwitchPitch meeting translates into actual business, although there are some success stories from past events.

For most small business owners, the chance to talk in-person with a big company is enough. For others, the event is a way to form connections with fellow entrepreneurs.

“These global companies can be impossible. You know they have real needs, but it is like circling the walls of Jericho to get in,” said Morris Panner, chief executive of Phoenix-based Dicom Grid, which lets patients and doctors share medical reports through an app.

“I’m actually following up with other start-ups,” said Katie Kirsch, chief marketing officer of Baltimore-based Sisu Global Health, which develops medical technology for emerging markets.

Panner said the event helped him forge unlikely partnerships. The American Cancer Society, an organization he viewed as a potential partner, did not have a need his business could serve, but Samsung potentially did.

As for big companies, the event was a window into the issues their peers face.

“It was interesting to get visibility into the problems that other companies deal with, because there’s a lot in common,” said Chris Lee, Samsung’s senior manager of technology sourcing.