Swinging is a group sexual practice engaged in by a minority of people infrequently. Our study includes 95 swingers (62 men and 33 women, average age 38±9.6 years) recruited via Internet French websites, mainly “www.netechangisme.com/”. Approximately half of all swingers included declare to be single (42%). Most are middle managers or skilled workers (45%) and higher level managers or other professionals (42%). As to sexual orientation, 67% of the swingers describe themselves as heterosexual (81% men, 42% women), 31% as bisexual (19% men, 52% women) and 2% as homosexual (0% men, 6% women) (P<10⁻³). Half of all the swingers (48%) state they go to swinging locations with their usual partner, 13% most of the time, 24% sometimes, and 15% never. The types of sexual activities engaged in are: threesomes (86%); soft-swinging (72%); swinging (60%); voyeurism (56%); candaulism (42%); exhibitionism (39%); gangbang (33%); same room sex (31%); and sadomasochism (19%). There is no significant difference of swinging practices based on sex or sexual orientation. The main characteristic of current swingers, as opposed to people who were swingers in the past (past swingers), is that they frequent swinging locations all or most of the time with their usual partner. Among the men, sexual practices which differentiate current swingers from past swingers include swinging and threesomes. Among the women, sexual practices which differentiate past swingers from current swingers include gangbang and voyeurism. The personality dimension sensation seeking, the frequency of alcohol and cannabis consumption and the lifetime prevalence of cocaine and ecstasy use are higher in the swingers than controls.