Finding qualified women to fill open  board seats shouldn't be difficult. But many companies struggle all the same.

It's not that there aren't plenty of women who would make fine additions to company boards; it's often more a question of entrepreneurs' limited networks. They simply don't know enough people, says Lesley Grossblatt, chief operating officer at theBoardlist, a Silicon Valley organization that was founded to help companies discover women candidates for board positions.

"The board search process has been inherently very closed," says Grossblatt. "Current board members reach out to trusted advisors, and most people's networks are very reflective of their own demographic."

And while many companies actively work to change this dynamic--by reaching out to organizations like theBoardlist, for instance--progress has been slow. Women hold just 6.8 percent of board seats at private tech companies, according to theBoardlist's research. At unicorn companies--those valued at $1 billion or more--women account for 10 percent of board seats. A staggering 80 percent of private tech companies have no women on their boards whatsoever.

The hope is that by pooling recommendations from Silicon Valley investors, executives and board members, theBoardlist creates a master list of qualified women to up the chances companies with an open seat find a woman to fill it. The organization--which was founded in July 2015 by Sukhinder Singh Cassidy, founder of video shopping platform Joyus--leans on executives or investors like StitchFix founder and CEO Katrina Lake and Airbnb co-founder and CEO Brian Chesky. They apply to become so-called Endorser Members on theBoardlist and as such help vet potential candidates. Companies with an open board seat and more than $5 million in annual revenue or venture funding can join theBoardlist to browse such candidates.

It can be hard to judge precisely if theBoardlist's strategy is working, as it's not an exact science. However, during the third quarter, five of the sixteen open board seats at tech companies were filled by theBoardlist candidates, according to a report released on Wednesday by the company. Further, in the second quarter, theBoardlist says two board members were chosen from its list. Deidre Bigley took a seat on stock photography site Shutterstock's board, and Betsy Rafael joined Shutterfly, an image-publishing platform.

"We want to give ourselves a pat on the back, but who knows. Lots of organizations have been beating the drum over the last year or so about the value of diversity on corporate performance," says Grossblatt.

Next theBoardlist is pushing to expand its own network beyond Silicon Valley. Over the coming year, it is meeting with tech community leaders in cities like Boston and Seattle to get more Endorser Members, and in turn candidates, on board.

"When you think about the problem of women in leadership in technology, there are so many places to balance," Grossblatt says. We could go all the way up the pipeline to STEM education for girls and young women. But this just happens to be where we had a very specific insight and an idea for how we could change the dynamic of how we get women on boards."