How to get more women on boards? Start with one.

October 17, 2013, 4:45 PM UTC
Mellody Hobson

FORTUNE — Women have been shown to be effective board members, so why aren’t there more of them?

Despite the strides women are making in the C-suite and the ballot box, gender diversity on corporate boards remains an intractable problem. The issue was brought to the fore earlier this month when Twitter filed its IPO and revealed that its seven-member board was made up entirely of men. Its explanation: no qualified female candidates.

At Fortune’s Most Powerful Women Summit this week, Ariel Investments President Mellody Hobson called that excuse, standard for major companies, “myopic.”

No women available with technical expertise? No problem, said Hobson, who sits on the boards at Starbucks (SBUX), DreamWorks (DWA), Estée Lauder (EL) and Groupon (GRPN). “Not every single person on the board of Starbucks knows everything about making coffee,” she said. “The people on the board of DreamWorks with me don’t all make movies.”

Her suggestion for diverse board candidates at Twitter: “My answer is anyone. Anyone. I mean that,” she said.

MORE: Complete coverage of the Most Powerful Women Summit

That might not be a bad idea. Recent studies have shown that having more female board members is good for more than optics. Controlling for other factors, gender diversity significantly increases profit margin. It’s also easy to see how at a company such as Twitter, where the majority of users are female, women’s voices could lend an added benefit. But Twitter is not alone in having a gender imbalance. Only 16.6% of board members at Fortune 500 companies are women, according to research by Catalyst.

So how do you fix the problem? Executives at Fortune’s MPW Summit this week had a few ideas.

Start with one.

Landing a board seat has a lot to do with networking, so one position is likely to lead to another. “After the first board position, it does get easier,” said Ilene Gordon, chair president and CEO of Ingredion.

It also helps to have at least one woman director to get other women to join. For her first five board jobs, Gordon was the first female member. From there, “What I pushed for was the second woman.” Progress can beget progress. “Having the first woman is key, and then from there you can push over time to get that balance,” Gordon said.

Companies want operating experience.

Lee Hanson, VC of global financial services and CEO & Board of Directors Practices at Heidrick & Struggles, laid out what companies today are looking for when they recruit. Often, companies are actively looking for diversity on boards. But more than anything, it helps if a candidate has operational experience as a general manager. Boards also prioritize candidates with technology experience (particularly in Silicon Valley) and candidates who are foreign nationals as well as Americans who have lived abroad.

For board hopefuls: Figure out what you could add, then go for it.

Susan Decker is a director at Berkshire Hathaway (BRKA), Costco Wholesale (COST), Intel (INTC), and LegalZoom (LGZ). Of getting those assignments, she says, “it was all relationships that I had built over time.” But if that feels like a catch-22 about needing connections to get connections, it’s possible to build those relationships from scratch, Decker says.

“Decide what’s important to you and what could you add, and then figure out who the board members are and figure out who you know who knows them,” Decker said. “Then get an introduction.” After that? “Then you have to perform,” she says. “And if you perform well, there will be lots of opportunities.”