Half of married Italians have had affairs and the number is growing, according to a survey by the Italian Association of Family lawyers.
Men are less faithful than women: 55 percent of husbands admit to having an affair, compared with 45 percent of wives, according to the research.
The northern Italian city of Milan is Italy's 'marital infidelity' capital and social networking sites, especially Facebook are stoking 'serial adultery', the research found.
Another culprit is Gleeden.com, which describes itself as 'the premier international dating website for married people' and to which 90,000 Italians are signed up. The site, which has versions in 158 countries, has special 'alarm' button allowing visitors to disconnect should their spouse walk in.
Most extramarital affairs (60 percent) happen in the workplace and the trysts typically take place during 'lunchbreaks' between 2 and 3 p.m.
Seven out of 10 affairs are one-off flings and the rest more long-term relationships. The biggest philanderers are men in their fifties who dally with younger women.
'The figures reveal a major crisis in marital relations,' said the association's president, Gian Ettore Gassani.
'Besides domestic violence, this stems from new customs which bring Italy more into line with northern European countries.'
The average age of the cheating spouse is 44 - greater than in the past - and nowadays around half the cases of infidelity are tolerated by long-suffering partners, the survey found.
In half of cases, cheating partners are caught out through indiscreet mobile phone text messages, while emails betray one in five and a further one in 10 are given away by anonymous letters, according to the survey.