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Book Summary: The Confidence Code – The Science and Art of Self-Assurance – What Women Should Know

Why is there a confidence gap between men and women? The authors of “The Confidence Code” went on a quest to find out, by talking to women who excelled in sports, business, and politics. They interviewed academics who studied behavior and genetics. The results surprised them and pointed to a path, which you’ll find in this book review, that all women can follow to become authentically confident.

Learn to be more confident without acting like a jerk.


  • Worry less and do more
  • Become more confident in a way that feels authentic
  • Raise confident daughters


Katty Kay and Claire Shipman, journalists and authors of Womenomics, interviewed successful women in a range of fields including sports, politics and business – and discovered that many, even the most successful, lack confidence. The authors investigate whether men really have more confidence than women. They find that confidence trumps competence at work. For example, women often lack the confidence to voice their opinions, even though such reticence hurts their chances for promotion. Women prove especially reluctant to negotiate for better salaries and often ask for less money than men request. After interviewing geneticists for insight, the authors report that confidence has a strong genetic component, though environment also matters. While much of their treatise is discouraging, it does offer hope. With effort, you can become more confident. Boost your confidence by speaking up and taking strategic steps; do not overthink your decisions. We recommend the authors’ insights and research to women – and men – who struggle with a lack of confidence, and to parents who want to instill confidence in their children.

Book Summary: The Confidence Code - The Science and Art of Self-Assurance - What Women Should Know


  • Women are making great strides in business, politics, economics, sports, and more. Studies show that more senior women at a company means more profit.
  • Yet many women, regardless of their level of success, lack confidence.
  • Women often underestimate their abilities and undermine themselves by attributing their success to luck or fate rather than to their own hard work and perseverance.
  • Confidence is often more important than competence, especially in the workplace.
  • Women hesitate to negotiate for better salaries and, when they do, they ask for less money than men request.
  • Confidence is partly genetic; environment also plays a role.
  • Society encourages boys to take risks and explore, and encourages girls to be quiet and well behaved.
  • Build children’s confidence by encouraging them to take risks in small steps.
  • Men and women have slightly different wiring. Women are prone to ruminate.
  • To build self-confidence, “Think less. Take action. Be authentic.”


Why do women sometimes lack the confidence to even try to reach their goals?

Why do so many high-achieving women doubt they deserve their success? How come so many women hold themselves back? Authors Katty Kay and Claire Shipman crisscrossed the country seeking answers. This is what they found:

  1. Working hard is not enough. Success depends more on confidence than competence.
  2. Do more and think less. Women tend to worry and ruminate, but taking action is the key to developing confidence.
  3. Confidence is partly hard-wired. Genes influence confidence levels, but you can rewire your brain at any time.
  4. Why women are less confident than men. Hormones, structural brain differences, social expectations, and bias all play a role.
  5. Nurturing confidence. Forget about the empty praise of the self-esteem movement. Instead, build resilience by risking failure.
  6. Confidence-building habits. To boost confidence, get in the habit of taking reasonable risks, reframing limiting thoughts, and thinking about how your work will enhance other people’s lives.
  7. Pass it on. Help your daughters and women friends and colleagues become more confident by encouraging them to take action.
  8. Do it your way. You don’t have to imitate men to be confident.

Working Hard Is Not Enough

Even women with exceptional accomplishments, who seem supremely confident on the surface, are often filled with self-doubt. Most women tended to overthink, ruminate about mistakes, go into people-pleasing mode, attribute their success to luck, feel like imposters, hesitate to speak up, or over prepare, no matter how much they’ve accomplished in their lives.

Christine Lagarde, who runs the International Monetary Fund, says she talked about being over prepared with Angela Merkel, the chancellor of Germany and one of the most powerful women in the world. They both felt they had to understand everything completely from every angle to be sure they wouldn’t make a mistake.

There’s a confidence gap between women and men. Research shows that women talk 75% less when they are in groups where men outnumber women. Men expect to earn higher salaries. Women worry more than men about what will happen if they fail and let their doubts hold them back more often.

The gap may be even more significant than most people realize. A study at the Haas School of Business at UC Berkeley found that it’s confidence, not competence, that is the most important prerequisite for success. Confidence is also a key part of happiness and feeling fulfilled in all aspects of life.

Do More and Think Less

You don’t have to be an aggressive jerk to be confident, and confidence is not only about feeling good about yourself. Confidence is not the same thing as self-esteem, optimism, self-compassion, or self-efficacy, although it’s related to all of those things.

Confidence is about believing you can get the results you want by taking action. The authors visited a lab where a neuroscientist tested rats to see how confident they were. The rats were put into a box where they had to make decisions about which way to turn. If they picked the correct direction, they got a reward. The catch was that they had to wait for the reward. The rats who were confident about their decisions waited. Those who were doubtful gave up, went back, and had to start all over again, losing all the time they had already invested in waiting.

Confidence comes from mastering a skill. That doesn’t mean trying to be perfect. It means enjoying challenges and not letting obstacles stop you. Mastery starts a positive snowball effect: When you master one thing, you gain the confidence to try another.

When you are confident, when you believe you can succeed, you turn your thoughts into actions. Doubts and worries paralyze you, but confidence propels you to do what you need to do to get the things that you want.

Confidence is Partly Hard-Wired

The authors’ next quest was to find out if confidence was something that we are born with, or if it was something we could learn. They visited another test lab, where researchers found that a gene that regulates monkey serotonin directly affected confidence.

Monkeys who had the high-serotonin version of the gene were more resilient, took more risks, and grew up to be leaders of their group. Monkeys with the lowserotonin version tended to be more fearful and clingy, and they avoided risks.

Twin studies in humans also showed there’s a genetic component to confidence. In the studies, identical twins were more likely to have similar levels of confidence than fraternal twins. The relationship between genes and confidence may be even higher than that between genes and intelligence.

Although genes account for about 25% to 50% of your confidence — which is quite a bit — no matter what genes you have, you can still choose to be more confident.

Your brain has something called neural plasticity. That means you can change the hard-wiring in your brain throughout your whole life. New experiences, cognitive therapy, and meditation can all reroute your neural pathways or create new ones that overlie the old ones.

Why Women Are Less Confident Than Men

Prejudice and bias account for part of the reason why women lag behind men in average income and in filling top leadership roles. In one classic example, when orchestras started auditioning musicians behind screens so the evaluators couldn’t see the musicians’ gender, the percentage of women hired shot up.

There are other factors that contribute to the confidence gap. Girls get rewarded for being good. That makes them excel at school, but the rules change after graduation. The workplace rewards aggressiveness — or at least it does for men.

Women also do things to themselves that undermine confidence. Women tend to be sensitive to what other people think, be thin-skinned about criticism, ruminate about problems, overthink relationships, be self-critical, believe they are personally responsible for bad results, attribute good results to luck or other people, and be perfectionistic.

Because these are self-imposed habits, you can change them. You can create new positive cycles of mastery and confidence.

One brain researcher performed tens of thousands of brain scans. He found men’s and women’s brains, while mostly the same, had some differences. Women tended to use both hemispheres of the brain more than men do. This is an advanced use of the brain and helps with multitasking. Women also tended to produce less serotonin, which made them more anxious. And women had more activity in brain regions associated with worry and stress.

Hormonal differences also play a role, with testosterone tied to taking risks, focusing on winning, and feeling powerful. Estrogen encourages connecting with others and avoiding conflict and risk.

Testosterone doesn’t necessarily create more successful outcomes in today’s business world, though. For example, a study showed that female hedge fund managers tended to trade less often than men and had results that were three times better.

It’s not known to what extent these brain differences are inborn or are the result of men’s and women’s different experiences. Either way, women can learn to use these differences to their advantage.

Nurturing Confidence

The self-esteem movement has not done girls and women any favors. When children get rewarded for everything, they lose the opportunity to experience failure and learn how to recover and keep going. When overpraised children grow up and enter the work world, their confidence — which is based on praise and not on real accomplishments — can shatter.

To become confident and resilient, children need to practice working hard, taking risks, being determined and, sometimes, failing. This can be hard for parents, who want to protect their kids.

Adults can become more confident if they believe they can always increase their knowledge and improve their skills. Women tend to think that they are either good or bad at specific skills, such as math, leadership, and investing. They believe their talents and abilities are static and won’t change. Men tend to think they can always learn more and get better.

If you believe you can learn new things, then you are more likely to take a chance and try doing them. It’s the doing that creates mastery, which is so closely intertwined with confidence.

It also helps to focus on the internal feeling of satisfaction that comes when you do a good job and not just on praise and other external rewards. You are more likely to take beneficial risks when you are not as concerned about losing other people’s approval.

Women can develop more confidence by choosing to take actions and make decisions. It takes ongoing hard work and resisting limiting beliefs about what you can’t do.

Confidence-Building Habits

In the tech world, “failing fast” is a popular technique. Instead of refining a product until it is nearly perfect before releasing it, businesses that “fail fast” throw things together quickly, unleash them on the world, and then get rid of whatever doesn’t work.

This is a good model for women who want to build confidence. Taking action is the key to becoming more confident. You don’t have to take huge steps all at once. The actions and risks can start off small and then build on each other. Practicing self-compassion by accepting your imperfections makes it easier to risk failure.

Beware of cycles of negative thoughts. Challenge these thoughts by writing them down and then reframing them in a positive or neutral way. For example, if you have the self-attacking thought, “Why do I still have so much left to do? What is wrong with me?” you could reframe that as “I’m doing a pretty good job juggling everything, considering how much I have on my plate right now.”

You can also increase confidence by turning your focus outward. Instead of worrying in excruciating detail about how you will handle a certain project, focus instead on how that project will help other people.

Sometimes, you should put the focus on yourself, but put it on your accomplishments instead of on your faults. Many women get into the habit of being selfdeprecating, and that can backfire.

Meditation is a healthy habit that can increase confidence by shrinking the part of your brain that generates fear. Other confidence-building habits are expressing gratitude, breaking big tasks down into smaller pieces, getting enough sleep and exercise, being authentic, and spending more time with friends.

Pass It On

Instead of just telling children they can be anything they want to be, help them develop the confidence to take risks, to keep going after they experience failure, and to struggle to master a skill.

Be a good role model. Let your kids see you working hard. Encourage your daughters to be independent. To help prevent perfectionism, don’t praise your daughters excessively for their good behavior or criticize them too much for their bad. Let them know you make mistakes, too, and that’s OK. Encourage them to develop interests in science, math, and sports.

Help the adult women you know become more confident, too. Inspire them to aim higher. Encourage them to take action. Sometimes it’s helpful to give them a little push.

Do It Your Way

The authors have different personality traits. One is more decisive and more inclined to take physical risks than the other, but also more anxious about confrontations.

Intrigued by what they learned about confidence and genes, the authors ordered their own DNA tests — though not without some trepidation!

Since their confidence-related traits were so different, they expected the results from their DNA tests to differ, too, but that’s not what happened.

It turned out both had the same profiles for “worry” genes and for “nurturer” genes. They also had the same genes that coded for low serotonin. Their life experiences had outweighed their genes in forming their differing types of confidence.

They considered all the research they had done for this book and concluded that having confidence is equally important for men and for women, but the genders express their confidence in different ways.

Women don’t have to try to imitate men, to put on airs of macho bravado. You don’t have to act like a jerk to be confident! Instead, you can build on your own natural advantages. You can be authentic and express confidence that comes from your core. It’s all within your reach.


Social Confidence

Despite women’s great societal strides, their self-doubt persists. Women believe that hard work and effort pay off, even though that isn’t always the case. Many women have seen less-competent men receive promotions and higher earnings. Confidence seems to trump competence; research found that “success correlates more closely with confidence than it does with competence.”

“The Economist…called female economic empowerment the most profound social change of our times.”

In some arenas, like basketball, you can’t fake confidence. Monique Currie and Crystal Langhorne, forwards for the WNBA’s Washington Mystics, are commanding on the court. But Currie admits to struggling with a lack of confidence. As she says, “You have to believe in what you can do and you have to believe in your ability.” Langhorne feels each loss and hates to let her fans down, but adds, “With guys, if they had a bad game, they’re thinking, ‘I had a bad game.’ They shrug off the loss more quickly.”

“Women earn on average 77 cents for every dollar earned by a man. Four percent of CEOs in the Fortune 500 are women. Twenty of the 100 United States senators are women and…that is celebrated as a record high.”

The Mystics brought in coach Mike Thibault to invigorate the team. Having coached both men and women, Thibault has a unique perspective. He finds that “the propensity to dwell on failure and mistakes” creates female players’ “biggest psychological impediments” and often will “directly affect performance and confidence on the court.”

“Ruminating drains the confidence from us. Those negative thoughts and nightmare scenarios masquerading as problem solving, spin on an endless loop.”

The military demands confidence. Consider Officer Michaela Bilotta, one of 14 classmates at the US Naval Academy in Annapolis, Maryland, who served on the Explosive Ordnance Disposal (EOD) team. These specialists deactivate chemical, biological and nuclear weapons in hot spots around the world. Yet when researchers lauded Bilotta, she demurred as if she somehow hadn’t earned her position, despite knowing that she did.

“The confidence gap is a chasm, stretching across professions, income levels and generations, showing up in many guises, and in places where you least expect it.”

United States Secretary of Labor Elaine Chao, who served under President George W. Bush, emigrated from Taiwan to the US at age eight. While confident, she says, “My fear was that the newspapers would have blaring headlines like: ‘Elaine Chao Failed, Disgraced Whole Family’.” Chao arrived in New York speaking no English , so she was an easy target for teasing. “Some adversity, if it doesn’t break you, does make you stronger,” she says.

Confidence and Coin

In 2011, researchers at the UK’s Institute of Leadership and Management asked British women how confident they were in their professions. Fifty percent reported feelings of self-doubt compared to fewer than a third of the men interviewed. American women don’t fare much better. Carnegie Mellon economist Linda Babcock, author of Women Don’t Ask, discovered that men negotiate their salaries four times more often than women; and when women discuss their salaries, they ask for 30% less than men request. Professor Marilyn Davidson of England’s Manchester Business School found similar results. She surveyed her students about their expected salaries five years after graduation. Her male students think they deserve to earn far more than her female students anticipate earning. “Women effectively believe they are 20% less valuable than men believe they are.”

“Confidence is not…feeling good about yourself, saying you’re great and can do whatever you want to do.”

In 2009, Cameron Anderson, an expert on overconfidence who teaches at the University of California, Berkeley, asked 242 students about historic events and names. Some were real; others, he made up. The students who misidentified the most made-up people or incidents as actual were those with the “highest social status.” This indicates that “when people are confident, when they think they are good at something, regardless of how good they actually are,” it affects their “nonverbal and verbal behavior.”

“Of all the warped things that women do to themselves to undermine their confidence…the pursuit of perfection [is] the most crippling. Nothing kills confidence like perfectionism.”

Confidence also can explain why some employees are promoted more quickly. In Anderson’s study, lack of competence didn’t seem to matter. His most-confident students didn’t alienate their classmates even when they made mistakes because they genuinely believed in themselves.

Confidence and Genetics

Neuropsychologist Steve Suomi of the US National Institute of Health has spent more than 40 years studying nature-versus-nurture issues by tracking the personality traits of rhesus monkeys. Like humans, monkeys exhibit a range of emotions. Humans share 90% of their genes with monkeys, but one of these shared genes particularly fascinates researchers: the serotonin transporter gene, SLC6A4, which “directly affects confidence.” Serotonin is a hormone that influences mood and behavior, and having higher levels of it produces more calm and happiness. This gene comes in different forms. A gene with two short strands links to poor processing of serotonin; a gene with one long strand and one short strand is better, but not great. A gene with two long strands processes serotonin most efficiently. Those monkeys with longer strands of SLC6A4 were more social, took more risks and showed leadership traits. Monkeys with shorter strands were less social, more fearful and afraid to take risks. In studies of how much environment affects these monkeys, Suomi placed monkeys whose genes indicated they’d be anxious or fearful with nurturing foster mothers, and the monkeys overcame those negative traits. These monkeys were “genetically challenged,” but they did well when great mothers raised them.

“When praised, reply, ‘Thank you. I appreciate that’.”

Suomi and other experts, such as Kings College, London, behavioral geneticist Robert Plomin, agree that confidence partially links to genetics. Plomin asked students to complete 15,000 sets of standard IQ tests, and tests in math, writing and science. He then asked them to rate their confidence levels in each subject. “The students’ self-perceived ability rating, or SPA, was a significant predictor of achievement, even more important than IQ.”

“Confidence that is dependent on other people’s praise is a lot more vulnerable than confidence built from our own achievements.”

Genetic research into personality traits like confidence is in its infancy. Finding a gene that relates to confidence is unlikely, but gene combinations can create different cocktails of personality and intelligence traits. Confidence also involves cognitive function. Apparently, what matters is not whether people can do a task, but whether they believe they can do it.

“By failing a lot…when we’re young, we…are better-equipped to think about the big, bold risks later.”

Suomi’s research confirms the “orchid theory” – that some monkeys and humans develop sensitized genes and become more sensitive to their environment. Developmental psychologist Bruce Ellis and developmental pediatrician W. Thomas Boyce compare children to dandelions that can withstand any environment. New research suggests that adults should view “nondandelion children,” in effect, “as orchids: trickier to raise, but if nurtured in the right environment, able to excel beyond even their sturdier dandelion counterparts.”

Double Standards and Self-Sabotage

School is where girls learn to “keep their heads down, study quietly and do as they’re told.” While school rewards girls for being good, staying calm and not fighting, it encourages boys to be messy, explore and take risks. Girls shun “making mistakes and taking risks,” though that behavior is crucial for building confidence. Boys chalk failure up to a lack of effort; girls tend to think they lack skills.

“The beauty is that when you fail fast or early, you have a lot less to lose.”

Research praises the confidence-building benefits of sports. In 1972, the US passed the Title IX law to ensure equal funding for male and female athletic programs in public schools. Studies of the law’s impact found that “girls who play team sports are more likely to graduate from college, get a job and be employed in male-dominated industries.” The research uncovered “a direct link between playing sports in high school and earning a higher salary in later life.” Today, more girls play high school and college sports than ever, but they also quit more quickly than boys do. Because teenage girls often experience low self-esteem, they’re more likely to drop out of athletic activities. This is “a vicious circle: They lose confidence so they quit competing, thereby depriving themselves of one of the best ways to regain it.”

“We may not realize it but we all give confidence inordinate weight and we respect people who project it.”

The world of work not only doesn’t reward women for being polite and quietly working hard, it actively punishes them for being aggressive. Linda Hudson, president and CEO of BAE systems, the US division of the global defense contractor, says that if women enter “the boss’s office with unsolicited opinions, speak up first at meetings and give business advice above our pay grade, we are either disliked or…labeled ‘a bitch’.” People assume men are “competent until they prove otherwise.” This assumption works “the other way around” for women. Psychologists Claude Steele and Joshua Aronson call Hudson’s dilemma the “stereotype threat,” a phenomenon they researched in the mid-1990s while investigating why African-American college students underperformed compared to white students. The same bias affects women, especially in science and math, in which, stereotypically, women don’t do as well as men.

The Cost of Likability

Women often sabotage themselves at work because they want to be liked. This quest for likability is costly, resulting in a $5,000 pay gap between young men and young women in their first five years of work after college. Because women hesitate to negotiate for better salaries, their pay gap widens over the years. Women tend to overthink situations. This rumination affects their professional and personal lives. Most women can relate to dissecting fights with friends or lovers or second-guessing simple decisions, such as getting a new haircut.

“The New Nurture”

Other cultures take a different view of parenting than Americans, and often encourage more independence and risk taking. Jane Wurwand, the British leader of the Dermalogica skin care company, walked home from school alone at age four and a half. Christine Lagarde, the French managing director of the International Monetary Fund, babysat her younger brothers when she was four. Both say their parents’ early confidence helped them. To give children confidence, those who nurture them need “to toughen up, to shake off that warm and fuzzy image.”

“What it means to be confident – and what it does for us – that’s the same for women as it is for men. Doing, working, deciding and mastering are gender neutral.”

For 20 years, the self-esteem movement has preached that everyone is wonderful and deserves a prize. But parents bolstered their kids’ self-esteem so much that children began to fear failing. Parents have conditioned kids to believe they can do anything, and so they run into problems as adults when reality collides with that perception. Gradually exposing kids to risk builds confidence, says University of Michigan psychologist Nansook Park. He advises parents to talk to their kids about their successes and failures, and to encourage them to court risk in small steps. When they fail, ask what they learned and how they can improve their results next time.

“Even if your daughter likes the pink Legos or lacy ballerina dress, there’s no reason you can’t steer her toward math and science at the same time.”

Children learn more from seeing your example than from being told. Don’t fall into the trap of rewarding “good girl” behavior. Girls quickly pick up subtle clues that being quiet and neat wins your approval. This can lead to low self-confidence and an overreliance on external approval. High-achieving girls can be prone to perfectionism. To diminish perfectionism, offer moderate, specific praise. Don’t hide from your mistakes; laugh at them and show them to your daughters.

Boosting Your Confidence

Boost your confidence by failing fast, stepping out of your comfort zone, not overthinking and by reframing negative thoughts. Failing fast, a business strategy that’s popular in technology circles, applies to everyday life. Instead of trying to perfect a single product, put a bunch of products out there to see what consumers buy, and trash the rest. Take action even if it means opening yourself up to failure. Overanalyzing every word, sound or gesture won’t change a situation’s outcome. Realize that most people focus on their own drama and aren’t worrying about what you do.

Avoid “negative automatic thoughts,” such as, “That dress was too expensive. Why did I waste my money?” or “I’ll never finish this project; I knew I wasn’t up to it.” Write down your automatic negatives and reframe them in a neutral or positive way. Reframing will be awkward at first, but practice until it becomes a habit.

Build confidence by meditating, being grateful, breaking larger tasks down into smaller ones, getting more sleep, exercising and socializing. At work, practice taking “power positions,” like sitting up straight, nodding your head, and taking a seat at the table rather than in the corner of the room. Finally, be yourself. Be authentic.


Becoming more confident is a decision that you can make at any time in your life. You are not limited by your genes or your early experiences because you can change the pathways in your brain. The most important thing is to take action, even if you have to push yourself. You can start with small steps. Act more, think less, and stay authentic. Always remember:

  1. Working hard is not enough. Success depends more on confidence than competence.
  2. Do more and think less. Women tend to worry and ruminate, but taking action is the key to developing confidence.
  3. Confidence is partly hard-wired. Our genes influence our confidence level, but we can rewire our brains at any time in our lives.
  4. Why women are less confident than men. Hormones, structural brain differences, social expectations, and bias all play a role.
  5. Nurturing confidence. Forget about the empty praise of the self-esteem movement. Instead, build resilience by risking failure.
  6. Confidence-building habits. To boost confidence, get in the habit of taking reasonable risks, reframing limiting thoughts, and thinking about how your work will enhance other people’s lives.
  7. Pass it on. Help your daughters and women friends and colleagues become more confident by encouraging them to take action.
  8. Do it your way. You don’t have to imitate men to be confident.

About the author

Katty Kay is an anchor on BBC World America. Claire Shipman is an ABC News and Good Morning America correspondent. Their previous book, Womenomics, was a New York Times bestseller.

Katty Kay is BBC World News America’s Washington, DC, anchor and contributes to NBC’s Meet the Press. Claire Shipman covers international affairs and women’s issues for ABC News and Good Morning America. They wrote Womenomics: Work Less, Achieve More, Live Better.