So soon as we turned with our drinks, couples close at hand smiled at us and greeted us and expressed admiration for my get-up. None of them particularly took my fancy or, if the women did, the men did not and vice versa.

This is one of the curses of the swinging world. Rich, ugly older men often have lovely young wives. Unless these make it plain that their husbands are happy for them to play alone, the deeply shallow like me who value physical beauty must renounce these lovely, limber creatures - if we are not to have to explain to the men that… er, sorry, really, I just happen to have developed a strangely selective headache.Gazing around the room, however, I was pleasantly surprised. Most of the people there were in their thirties or forties, but there were several couples in their twenties, including a few couples whom I would have admired and felt drawn to in any circumstances.

This was a ‘Couples Only’ party. Many clubs and swingers’ groups permit a limited number of single males to enter on specific nights. The usual convention in the clubs is that males are permitted on Friday nights and couples only on Saturdays.

The extent of selectivity imposed by each club varies widely. At Chameleon’s, for example, and at Liberation’s in Leicester, single males must submit photographs and lengthy forms before they are considered, and must then remain on a waiting list for six months or more before they will be admitted. Other clubs are less stringent in their requirements, particularly since single males must pay up to three times the entrance fee paid by couples. Single females, unsurprisingly, are always welcome.