Europeans who use social networking sites are increasingly concerned about their privacy.
A study by Survey Sampling International (SSI) found that more than 50% of Britons, Germans, French and Spanish were worried about identity theft and misuse of personal data.
Their biggest concerns were the risk of ID theft and being approached by unscrupulous advertisers without their consent.
Surveying a panel of more than 10,000 European consumers, SSI discovered that Germans (77%) were the most concerned about unsolicited advertisements.
Consumers in Spain (59%) and France (57%) also feared exposure to advertisers approaching them via social networks.
As many as 65% of Britons polled said they feared being the victim of an identity theft scam, followed by 51% of the French and 42% of the Spanish.
The least concerned about having their personal data stolen for fraudulent use were Germans (40%).
Despite their concerns, respondents were happy to share personal information on social networks.
Information such as photos, personal opinion and preferences were the types of personal data that respondents preferred to share, closely followed by the sharing of personal contacts.