SAN FRANCISCO >> For months, technology companies have pursued Amy Chang.

The calls are relentless, with several feelers a month, said Chang, chief executive of Accompany, a Silicon Valley startup. Even when she declines the overtures, the tech companies and their agents keep coming back, asking the same question: Will you please join our board?

“I turned down 15 to 20 first meetings” about joining a company board this year, said Chang, 39, who was an executive at Google for seven years before founding Accompany, which makes an executive-briefing app. “This whole thing is so crazy.”

Chang eventually agreed to one invitation. In October she was appointed to the board of Cisco Systems, the behemoth Silicon Valley maker of networking gear. The role pays her a $75,000 annual retainer and gives her a grant of restricted stock worth several hundred thousand dollars. She is now the youngest of Cisco’s 11 board members by at least a decade, and one of four women.

Even by Silicon Valley standards, where recruiting wars are legion, attracting women to join tech company boards has become intense. While many companies still want the highest-profile women in the industry — think Sheryl Sandberg of Facebook or Meg Whitman of Hewlett Packard Enterprise — a new pool of candidates is also being hotly pursued. And those women are younger, tend to be ethnically diverse and have grown up in digital businesses for much of their careers.

The competition for these women is thriving as tech companies are under growing pressure to diversify their boards. While Twitter and other tech companies have taken steps to add more women to boards, the tech industry still lags others in gender diversity. Among Silicon Valley’s 150 largest companies, only 15 percent of board seats were filled by women in 2016, compared with 21 percent for companies in the Standard & Poor’s 500 Index, according to the research firm Equilar.

A lack of diversity permeates many parts of the tech industry — the overall workforces of companies like Facebook, Google and others strongly skew male — but boardrooms are a particular focus because they are power centers that can help spur broader changes. Board positions are often coveted for their prestige and big paychecks; median pay for directors at large public companies was $270,000 in 2015, according to Equilar.

Chang is one of the new generation of tech women who are now being courted to close that gap. Others include Stacy Brown-Philpot, chief executive of TaskRabbit, a San Francisco startup that connects people to cleaners, handymen and others who do household tasks. Brown-Philpot was appointed to her first public company board, HP Inc., in 2015.

Also in demand are Selina Tobaccowala, who runs the startup Gixo, and Clara Shih, chief executive of Hearsay Systems, who joined the board of Starbucks five years ago, at age 29, executive recruiters said.

“Boards are looking at diversity across multiple dimensions, such as gender, ethnicity, age and unique skill sets,” said David Chun, chief executive of Equilar, which tracks board candidates and executive compensation. “If you can bring a number of these different attributes and perspectives to the boardroom, you’ll be in high demand.”

The clamor for these women has spread beyond Silicon Valley’s large public tech companies to privately held startups as well, some of which could emerge as the next public giants. Glenn Kelman, chief executive of Redfin, a closely held online real estate brokerage, said he sometimes had to mount “pitched efforts” to attract female candidates to his company’s nine-member board because many other startup chief executives were after the same people.

“A lot of executives are trying to do this,” Kelman said. “If I dillydallied, suddenly everyone was recruiting” the same person.

In November Redfin brought on two new directors, including Julie Bornstein, chief operating officer of Stitch Fix, an online personal stylist service. Bornstein is the second woman serving on Redfin’s board. In 2014 the company added Tobaccowala, a co-founder of Evite who was later a top executive at the online polling company SurveyMonkey.

Bornstein, 46, a former chief digital officer at Sephora, said she had gotten 30 or 40 calls to discuss joining a corporate board over the last few years, even though she had never sat on one. Before becoming a member of Redfin’s board, Bornstein said, she also talked to two public companies about a board spot, though she lost out to other women for those positions.

Yet many hurdles still prevent women from joining more tech boards, Bornstein said. As she interviewed at companies about board seats, she said, she found that many directors typically stuck to their own networks of acquaintances for candidates. That generally led to looking at the same people over and over again.

As a rule of thumb, boards also want experienced members. Part of the reason Bornstein said she did not land other board positions was because “they couldn’t get their head around someone who hadn’t been on a board before.” Because there are “fewer natural high-profile women in tech,” she said, “it requires taking bets on new people.”