Women prefer 'men who are kind'.
"Signs of altruism have an enormous effect on women looking for a boyfriend," according to Ros Fewster from London, who found love though a dating agency.
"When I saw on my boyfriend's listing that he had worked with disabled groups, that definitely worked for me. "
She disputes the popular notion that women prefer to date 'jerks' and that 'nice guys finish last'.
Her view is supported by research published in the British Journal of Psychology.
The Canadian study found that women preferred men who appear to be generous.
This applied whether they were seeking a long term relationship or just one date.
But for men it was different.
While they still valued altruism in a long term partner, they found it slightly off-putting when looking for short term relationship.
Over 300 volunteers, half men, half women, were shown dating profiles, including photographs
They were asked to rate them for long term relationships or short term dates.
Some of the profiles were subtly modified to suggest the potential date was a kind person.
"In some of the profiles we gave hints to indicate kind, altruistic interests such as 'I enjoy helping people' and 'I volunteer at the food bank'," says the author, Dr Pat Barclay from University of Guelph, Canada.
"We found that women showed a strong preference for relationships with altruistic men in this study, even though the clues to altruistic traits were fairly subtle."
He explains this in evolutionary terms:
"This suggests that women are attuned to generosity, and that altruism serves a purpose in mate selection.
"If a man is kind and generous towards others - even strangers - then there's a good chance that he'd make a good and generous parent."
This finding is not surprising, according to Dr David Lewis, a member of the British Psychological Society and author of 'Loving and Loathing: the Enigma of Personal Attraction'.
"We know that women are often drawn to men who have masculine characteristics but with some femininity, such as soft hair on their forearm or longer than usual eyelashes," he said.
Altruism in men could also be seen as a "softening of their maleness," he added.
But he thinks that attraction is likely to be affected much more by appearance than by whether someone seems kind.
He says that people make up their mind about someone else incredibly quickly, often in the first second of meeting.
Then they seek to justify their initial impression.
“ We know that women are often drawn to men who have masculine characteristics but with some femininity, such as soft hair on their forearm or longer than usual eyelashes ”
But Dr Viren Swami, a specialist in interpersonal attraction from the Department of Psychology at the University of Westminster, disagrees.
He has studied how first impressions change when people subsequently interact.
He found that although physical factors, such as facial appearance and weight are initially important, they are quickly outweighed by personality.
"Our research has found 'agreeableness' to be particularly important to whether people are attracted to each other," he said.
Altruism could be regarded as one component of agreeableness, he added.
Dr Swami believes people may find altruism attractive in potential mates for cultural rather than evolutionary reasons.
"Most of us value altruism," he said. "We like people who are kind."
But what of the finding that men don't care about altruism when seeking partners for a quick fling?
"This could be because men fear that altruistic women will be too interested in other things and not enough in them," said Dr Lewis
"Men are very egotistical and see themselves as the sun in their own world. "
How does this impact in the world of dating?
Do people think they would be more attractive to potential partners if the present themselves as kind, caring and generous?
Ros Fewster thinks some men do try to play the altruism card on dating sites.
"While my boyfriend is a genuinely lovely person, I think some men play up their altruistic qualities when writing their listing because they think that will make them more appealing.
"Women don't tend to do this because men often take it for granted that women are kind. Women often think men are looking for other things.
"But men have to work harder to prove that they are not just after sex. "
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