Stereotypes bedevil the hiring process and they torment ambitious professionals in their careers. But they're impossible to eradicate. Why? Because stereotypes are energy-saving devices, mental shortcuts that allow us to extrapolate a great deal from a single detail.

Like cliches, they wouldn't persist if there weren't some truth in them. But in professional development, stereotypes are dangerous because they box you in and limit what people think you can do. Percy Barnevik, the esteemed CEO of ABB, once maintained that companies use only five to 10 percent of their employees' capacity. Stereotyping people is one way we obscure the rest.

Stereotypes are infuriating because they're insidious, we often don't even see them developing and they're based on biases and beliefs we have no control over. When we feel them being applied to ourselves, we get mad — but it's smarter to learn how to recognise them and how not get sucked into confirming them.

Research repeatedly shows that stereotypes are a major cause of the gender gap — the failure of women to be paid and promoted at a rate equal to men. So what are the stereotypes that women's careers suffer from?

The Geisha: When you start out in your career, you're young, pretty and eager to please. But being too charming can make others think that's all you bring to the table. I once worked with a VP of marketing who spoke several languages, had worked in three different countries and was outstandingly capable. How did her boss evaluate her? "The great thing about Frances," he said, "is that she's so charming."

When the company made their biggest (and worst) marketing decision, she wasn't in the meeting. You don't need charm to make strategic decisions.

The Invisible Woman: You don't want to be trivialised as charming, so you keep your head down and just work like crazy. I did this in the early stages of my career. I usually had two jobs (one salary) and was always willing to take on extra. For years, this meant annual promotions. But as I reached the top of the ladder, no one really knew everything I did — and the final promotion went to one of the protégés I'd recruited. (Another job I wasn't paid for.) Everyone was very surprised when I left.

The Bitch: If you're not a pretty geisha or invisible, one day you'll be called a bitch. This is what happened to Pamela Matthews, a banker. "Things get dicey when you reach the more senior levels," she says. "If you're tough with juniors, or in meetings, you're a bitch. But you have respect. You have no friends at work and everyone talks behind your back, but you have respect." The problem, of course, is you get very lonely, and being isolated at work is risky.

The Guy: If you survive the first three stereotypes, you may finally become an honorary guy. The day my boss put his arm around my shoulder and said "Good ol' Margaret, she's one of the guys," I felt I'd finally made it. So many women tell me that the only way to succeed is to assimilate, not just in personal style — the helmet hair and dark suit — but in language, work styles and mindset. The more of a guy you are, the more comfortable men are around you, and you feel accepted. The problem is that this successful executive isn't you.

As I've studied women's careers over the last 20 years, I've seen these four stereotypes everywhere. I think they're inescapable: some lucky women escape a few of them but I don't think I've yet met anyone who dodged them all.

You can't avoid this but you can mitigate the damage: Be aware you're being stereotyped and recognise that this isn't your fault. The mind likes short cuts — but they miss out a lot. Don't believe in the stereotype or do anything that might reinforce it. This is more tempting than you might imagine; everyone tends to respond to the image of themselves they see others respond to. When women are perceived as bitches, it can make them even tougher and more alone; when women are treated as geishas, it's hard not to become more charming.

Cleave to the colleagues and friends who see the whole you. We all need people to remind us of the best that we can be.

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Blame Darwin. Or Darwinism. Some companies continue to believe that the way to get the best out of their workforces is to encourage competition. If we pit talented people against each other, the argument goes, the best will get even better.

The most extreme version of this that I've encountered is a digital agency where each team has its own profit and loss statement — and compensation is tied to it. They get paid more when they cut costs and rack up prices. When the opportunity for a new piece of work or a new client comes in, each team has to compete for it internally. This doesn't just incur tremendous waste. It means the company's priorities — team first, then company, then client — are completely upside down. But the real victim isn't just the client — it's the culture.

With this kind of organisation, you don't have colleagues, you only have competitors. In a zero sum game of business development, every victory represents someone else's failure. People don't feel nurtured, and the in-fighting (by all accounts) is toxic.

Companies that promote internal competition do so because they believe two things: that what everyone wants most is money, and that the best (or only) motivator is ego. As a result, they end up recruiting individuals for whom this is true. Team players either don't apply or exit screaming. I have a friend who worked there for awhile, attracted at first by his confidence that he was bound to excel.

"What I hadn't anticipated," he told me, "was that when I won, I felt awful. When I lost, I felt awful. No amount of money made up for it. Even the great work I got to do didn't make up for it. Every day, walking to the office, I'd feel my stomach tightening as I braced myself for another day as an asshole." I'm amazed when I encounter firms that still foster this kind of internal competition. I appreciate that their CEOs want everyone, always, to be improving their game — but I don't think this is the way to do it. When I worked in television, I was certainly aware of the (many) directors and products that were more talented than I. But I felt inspired by them and worked hard to develop my skills to their level. I didn't compete with them — and they certainly didn't compete with me.

Who, I wonder, truly believes that in-fighting is productive? Is it just the judges, who sit on the sidelines, or those who fondly imagine themselves always the winner?