Last year, shortly after the conclusion of Fortune Brainstorm Design conference in Singapore, a group of innovators got together and created Design Vanguard, a collective that has since crafted the Design Pledge, a code of conduct for designers and has been signed by 50 major corporations, including IBM, Apple and IDEO.

During a town hall session at this year’s Brainstorm Design conference, John Cary, author of Design for Good and one of the instigators behind Design Vanguard, described the pledge as simply reflecting some of the basic things that designers need to be doing, such as safeguarding against harm and ensuring their design can give a voice to the marginalized. “It’s not rocket science,” Cary said.

But simple is not the same as easy. Speaking from the audience, Sean Carney, chief design officer at Royal Philips, offered an example of when his company’s ultrasound business wanted to expand into Indonesia. The country’s infant and maternity death rates were high and Philips believed its ultrasound machines could help. Carney led a team to investigate whether the Indonesian market really needed to buy $250,000 ultrasound machines. It didn’t.

“There’s no power, no skilled labor, and people wouldn’t know how to use this machine,” Carney explained. He included the feedback in a report sent to company headquarters. Carney’s team concluded that if Philips really wanted to save babies, the company would need a different, and less profitable, solution.

“You do have to stick to your principles in design and speak up,” Carney said. But designers have only recently become empowered to speak up and influence company-wide decisions. Jenny Arden, director of transportation at Airbnb, shared an experience she had 11 years ago when she was hired by an auto company to sell car loans to low-income consumers who couldn’t afford the repayments.

“At that time, in the design world, we were just told to do our job,” Arden said. “Now, what I’m really proud of is that we have that seat and are able to say no.”

Advocates of so-called design thinking believe including designers and design processes at senior management levels can help corporations do more “good.” But designers aren’t infallible. The notion of design having “unintended consequences” emerged from conversations more than once during the course of the Fortune conference, which took place last week in Singapore.

As the town hall discussion broadened to the rest of the room, one participant rightly questioned whether designers should be moral arbiters. Adobe vice president of design Jamie Myrold said she didn’t disagree with the sentiment, adding that designers must maintain humility. “We need need to know that we don’t know everything,” she said, “and that should be okay.”

For more coverage of Fortune’s Brainstorm Design conference, click here.