I BEGAN THIS BOOK by acknowledging that women in the developed world are better off than ever, but thegoal of true equality still eludes us. So how do we move forward? First, we must decide that trueequality is long overdue and will be achieved only when more women rise to the top of everygovernment and every industry. Then we have to do the hard work of getting there. All of us—menand women alike—have to understand and acknowledge how stereotypes and biases cloud our beliefsand perpetuate the status quo. Instead of ignoring our differences, we need to accept and transcendthem.

For decades, we have focused on giving women the choice to work inside or outside the home. Wehave celebrated the fact that women have the right to make this decision, and rightly so. But we haveto ask ourselves if we have become so focused on supporting personal choices that we’re failing toencourage women to aspire to leadership. It is time to cheer on girls and women who want to sit at thetable, seek challenges, and lean in to their careers.

Today, despite all of the gains we have made, neither men nor women have real choice. Untilwomen have supportive employers and colleagues as well as partners who share familyresponsibilities, they don’t have real choice. And until men are fully respected for contributing insidethe home, they don’t have real choice either. Equal opportunity is not equal unless everyone receivesthe encouragement that makes seizing those opportunities possible. Only then can both men andwomen achieve their full potential.

None of this is attainable unless we pursue these goals together. Men need to support women and, Iwish it went without saying, women need to support women too. Stanford professor DeborahGruenfeld makes the case: “We need to look out for one another, work together, and act more like acoalition. As individuals, we have relatively low levels of power. Working together, we are fiftypercent of the population and therefore have real power.”

As obvious as this sounds, women have notalways worked together in the past. In fact, there are many discouraging examples where women haveactually done the opposite.

We are a new generation and we need a new approach.

In the summer of 2012, my former Google colleague Marissa Mayer was named CEO of Yahoo.

Like several of her friends and the Yahoo board, I knew that she was heading into her third trimesterof pregnancy. Of course, many men take big jobs when their wives are weeks away from giving birth,and no one raises it as an issue, but Marissa’s condition quickly became headline news. She washeralded as the first pregnant CEO of a Fortune 500 company. Feminists cheered. Then Marissa let itbe known: “My maternity leave will be a few weeks long, and I’ll work throughout it.”

Manyfeminists stopped cheering. Since taking such a short leave is not feasible or desirable for everyone,they argued that Marissa was hurting the cause by setting up unreasonable expectations.

So was this one giant leap forward for womankind and one baby step back? Of course not. Marissabecame the youngest CEO of a Fortune 500 company … while pregnant. She decided how she wantedto manage her career and family and never claimed that her choice should apply to anyone else. If shehad cut Yahoo’s maternity leave to two weeks for all employees, then concern would have been inorder. She did not do this, but she was still roundly criticized. Even a European cabinet memberweighed in.

Like any individual, Marissa knows best what she is capable of given her particularcircumstances. And as journalist Kara Swisher also noted, Marissa “has a husband who can actuallytake care of the child, and no one seems to remember that.”

Women who want to take two weeksoff … or two days … or two years … or twenty years deserve everyone’s full support.

As Marissa’s experience demonstrates, women in powerful positions often receive greater scrutiny.

Because the vast majority of leaders are men, it is not possible to generalize from any one example.

But the dearth of female leaders causes one woman to be viewed as representative of her entiregender.

And because people often discount and dislike female leaders, these generalizations are oftencritical. This is not just unfair to the individuals but reinforces the stigma that successful women areunlikeable. A perfect and personal example occurred in May 2012, when a Forbes blogger posted anarticle entitled “Sheryl Sandberg Is the Valley’s ‘It’ Girl—Just Like Kim Polese Once Was.” Hebegan his comparison by describing Kim, an early tech entrepreneur, as a “luminary” in the mid-1990swho never really earned her success, but was “in the right place at the right time [and was] young,pretty and a good speaker.” The blogger then argued, “I think Polese is a good cautionary talefor … Sheryl Sandberg.”

Ouch.

Kim and I had never met or spoken before this incident, but she defended both of us. In a publishedresponse, she described reading the blog post and how her “immediate thought was—how sad. Howsad that as an industry and a society we haven’t advanced over these past two decades when it comesto views on women and leadership. As with all the past lazy, stereotype-ridden articles like this one, itgets the facts wrong.” After correcting the facts, she continued, “Views like these are all toocommonplace, and part of a pervasive pattern that belittles, demeans and marginalizes women asleaders.”

So many other readers joined her in calling the post sexist that the blogger posted anapology and retraction.

I was grateful for Kim’s vocal support. The more women can stick up for one another, the better.

Sadly, this doesn’t always happen. And it seems to happen even less when women voice a positionthat involves a gender-related issue. The attacks on Marissa for her maternity leave plans came almostentirely from other women. This has certainly been my experience too. Everyone loves a fight—andthey really love a cat-fight. The media will report endlessly about women attacking other women,which distracts from the real issues. When arguments turn into “she said/she said,” we all lose.

Every social movement struggles with dissension within its ranks, in part because advocates arepassionate and unlikely to agree on every position and solution. Betty Friedan famously and foolishlyrefused to work with—or even to shake hands with—Gloria Steinem. They both did so much tofurther women’s rights. But what if they had been able to work together? Couldn’t they have furtheredthe cause even more?

There are so many of us who care deeply about these matters. We should strive to resolve ourdifferences quickly, and when we disagree, stay focused on our shared goals. This is not a plea for lessdebate, but for more constructive debate. In Marissa’s case, it would have been great to keep the focuson her breakthrough achievements. Thanks to her high-profile appointment, other companies mightconsider hiring pregnant women for big jobs, and expectant mothers might be more inclined to applyfor them. By diminishing Marissa’s accomplishment, the attacks diminished us all.

It is a painful truth that one of the obstacles to more women gaining power has sometimes beenwomen already in power. Women in the generations ahead of me believed, largely correctly, that onlyone woman would be allowed to ascend to the senior ranks in any particular company. In the days oftokenism, women looked around the room and instead of bonding against an unfair system, they oftenviewed one another as competition. Ambition fueled hostility, and women wound up being ignored,undermined, and in some cases even sabotaged by other women.

In the 1970s, this phenomenon was common enough that the term “queen bee” was used to describea woman who flourished in a leadership role, especially in male-dominated industries, and who usedher position to keep other female “worker bees” down. For some, it was simple self-preservation. Forothers, it reflected their coming-of-age in a society that believed men were superior to women. In thissense, queen bee behavior was not just a cause of gender discrimination but also a consequence of thatdiscrimination. Queen bees internalized the low status of women and in order to feel worthythemselves wanted only to associate with men. Often, these queen bees were rewarded for maintainingthe status quo and not promoting other women.

Unfortunately, this “there can be only one” attitude still lingers today. It makes no sense for womento feel that we are competing against one another anymore, but some still do. In certain instances,women question their female colleagues’ level of career commitment, aggressiveness, and leadershipabilities.

One study found that female professors believed that male Ph.D. students were morecommitted to their careers than female Ph.D. students, even though a survey of the students found nogender difference in their reported levels of commitment.

Other research suggests that once a womanachieves success, particularly in a gender-biased context, her capacity to see gender discrimination isreduced.

It’s heartbreaking to think about one woman holding another back. As former secretary of stateMadeleine Albright once said, “There’s a special place in hell for women who don’t help otherwomen.”

And the consequences extend beyond individual pain. Women’s negative views of femalecoworkers are often seen as an objective assessment—more credible than the views of men.

Whenwomen voice gender bias, they legitimize it. Obviously, a negative attitude cannot be gender based ifit comes from another woman, right? Wrong. Often without realizing it, women internalizedisparaging cultural attitudes and then echo them back. As a result, women are not just victims ofsexism, they can also be perpetrators.

There is hope that this attitude is changing. A recent survey found that “high-potential women”

working in business want to “pay it forward,” and 73 percent have reached out to other women to helpthem develop their talents.

Almost all of the women I have encountered professionally have gone outof their way to be helpful. When I was a lowly summer intern at McKinsey, I met Diana Farrell, a starconsultant, at a company-wide conference in Colorado. Diana had just spoken at a panel that Iattended and we bumped into each other afterward—where else?—in the women’s room. We endedup having a talk that continued beyond the sinks, and she became a close friend and trusted advisor.

Years later, she was one of the few who encouraged me to join Google.

The more women help one another, the more we help ourselves. Acting like a coalition truly doesproduce results. In 2004, four female executives at Merrill Lynch started having lunch together once amonth. They shared their accomplishments and frustrations. They brainstormed about business. Afterthe lunches, they would all go back to their offices and tout one another’s achievements. Theycouldn’t brag about themselves, but they could easily do it for their colleagues. Their careersflourished and each rose up the ranks to reach managing director and executive officer levels.

Thequeen bee was banished, and the hive became stronger.

I know that not every woman encounters this kind of positive female support, and yet oddly, weoften expect it. Most women don’t assume that men will reach out and help, but with our own gender,we assume there will be a connection. We imagine women will act communally and maybe we do soout of our own bias. Once in my career, I felt that a senior woman treated me poorly. She wouldcomplain about me and my team behind my back but would not discuss any concerns she had withme, even when I asked directly. When I first met her, I had high hopes that she would be an ally.

When she turned out to be not just unhelpful but actually spiteful, I was not just disappointed; I feltbetrayed.

Sharon Meers explained to me that this feeling of betrayal was predictable. Both men and womendo, in fact, demand more time and warmth from women in the workplace. We expect greater nicenessfrom women and can become angry when they don’t conform to that expectation. “I think that’s a bigpart of the protest about executive women being ‘mean’ to other women,” Sharon told me. “I think it’sabout a double standard we have when we look at female versus male superiors.”

I now recognize that had this senior woman been a man and acted the same way, I still would havebeen frustrated, but I wouldn’t have taken it so personally. It’s time to drop the double standard.

Gender should neither magnify nor excuse rude and dismissive treatment. We should expectprofessional behavior, and even kindness, from everyone.

Any coalition of support must also include men, many of whom care about gender inequality asmuch as women do. In 2012, Kunal Modi, a student at Harvard’s Kennedy School, wrote an articleimploring men to “Man Up on Family and Workplace Issues.” He argued that “for the sake ofAmerican corporate performance and shareholder returns, men must play an active role in ensuringthat the most talented young workers (often women …) are being encouraged to advocate for theircareer advancement.… So men, let’s get involved now—and not in a patronizing manner thatmarginalizes this as some altruistic act on behalf of our mothers, wives, and daughters—but on behalfof ourselves, our companies, and the............