Narcissists might be irritating attention seekers - but they are also annoyingly likely to be successful, according to researchers.
Even though their personality traits might seem negative, psychologists say their sense of superiority gives them a "mental toughness" not to give up.
An international team of researchers says narcissists tend to come out on top in education, work and romance.
Their "heightened sense of self-worth" gives them great self-confidence.
For psychologists, narcissism is one of the "dark triad" of malevolent personality traits, along with psychopathy and Machiavellianism - with narcissists having a tendency to be self-centred, vain, grandiose and to need the admiration of others.
But Dr Kostas Papageorgiou, from Queen's University Belfast, says research shows that narcissists are often socially successful and undeterred by rejection and their craving for attention can make them "charming" and highly motivated.
"If we could abandon conventional social morality - and just focus on what is successful," he says, then narcissism can look like a very "positive" trait.
"If you are a narcissist you believe strongly that you are better than anyone else and that you deserve reward," says the psychologist.
This might be unbearable for everyone else around them, but Dr Papageorgiou says this kind of boundless self-belief is also linked to being "mentally tough" and a readiness to "embrace challenges".
It's all about me
The "power" of narcissism is currently on public view, he says, in the prevalence of narcissistic behaviour in popular culture, whether on social media, reality television or in politics.
Dr Papageorgiou is part of a research team including academics from Goldsmiths, the University of London, King's College London, University of Texas at Austin and Manchester Metropolitan University, which used performance in secondary school exams to show how narcissists could overtake people who had more ability than them.
Using a sample of more than 300 young people identified as narcissists in secondary school in Italy, the researchers found that they tended to score much better in exams than would have been expected from other tests of their intelligence.
Psychologists said that as well as traits such as egotism and the need to dominate, these narcissists had high levels of resilience and determination.
They were not cleverer, but were more confident and assertive and were able to overtake students who otherwise would have more ability.
Dr Papageorgiou says this pattern of advantage at school carries through to university and work - and also in romance.
He says that narcissists are likely to attract more partners.
"They're quite charismatic. If you spend a lot of time trying to be charming and persuade other people, it might well make you more attractive, says Dr Papageorgiou.
He says there could even be an evolutionary element to what he says is a rise in narcissism, with narcissists having more sexual partners and passing on their genes to more people.
Dr Papageorgiou says about 60% of narcissism is inherited, with the rest shaped by the environment.
Narcissists can be "absolutely destructive for those around them", says the psychologist, but there is nothing inevitable about this and they can limit the impact of these character traits.
"You can control them, rather than let them control you," he says.
Dr Papageorgiou argues that such personality traits should not be seen as "either good or bad" but as "products of evolution" and "expressions of human nature".