In 2006, apparently almost half – 49 per cent – of divorcing couples in Britain employed private investigators to check up on their spouses’ fidelity, compared with 18 per cent in 2005. The figure is made up of 30 per cent women and 19 per cent men. Men brought about 69 per cent of adultery cases, women 31 per cent. According to a Kinsey Institute

К

20 to 25 per cent of men are unfaithful at least during their marriages, as opposed to 10 to 15 rent of women. Infidelity is cited as grounds for югсе in more than 150 cultures around the world. A study by the London School of Hygiene and Tropical Medicine revealed -#) that men and women in Britain were more ^ adulterous than the Italians or French.

‘Men marry because they are tired, women because they are curious;
both are disappointed.’ Oscar Wilde

Nena and George O’Neill’s bestseller Open Marriage (1972) introduced just that concept to 1970s America, in order to benefit marriage by freeing it from old-fashioned rules, but they did not necessarily recommend additional sexual partners.