Years ago, the best friend of Prince William's now-wife announced the opening of a swingers club in Scotland, since she is already leading one in London, Killing Kittens. According to Scotland, on Sunday, no man can enter the club — he can be brought only by a woman (or more).

Moreover, women are those who make the rules in such clubs. They represent 80 percent of customers. The clientele is very selective, aged between 18 and 45 years. Killing Kittens in London claims to reject 1 of 3 applications.

Club attire is mandatory and jeans are not allowed. Inside drugs are prohibited but clients can delight themselves with champagne. Condoms are strategically placed in all the rooms and the atmosphere lures the most comfortable positions and outfits.

After the talk and look of choosing potential partners, lovers retire in rooms where they "play," where cameras and mobile phones are completely banned.

For those who like this lifestyle, they think it is a healthier alternative than fixed online dating. And the customer does not lack finding these kinds of clubs.

But what is swinging and how can we find out what it's like to be a swinger?

Swinging is sex in a group and/or exchange of partner(s). All this is combined with a touch of exhibitionism, a gram of voyeurism and something crazy.

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This phenomenon is seen as an alternative lifestyle that involves participation in recreational activities, especially sex (or just sex). Some people do not approve of this type of behavior, dismissing it as abnormal. Value judgments belong to those who are swingers, though.

Where did swinging begin?

Swinging appeared in the ancient times in Alaska, northern Canada and a few tribes in Africa, in which married couples had no reluctance to share their partners. The beginnings of modern swing are found in the middle of the last century.

Swinging as a modern practice has its origins in an elite group of pilots on fighter planes of the American Air Force during the Second World War and the Korean War. The high rate of mortality led to the acceptance of the relationship between wives of pilots and other pilots. Prima media story about this phenomenon occurs after the Korean War in 1957, where the phenomenon is called "wife-swapping" (changing wives).

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Although reported as a negative, the audience was receptive to the idea. And so, in 1960 there were over 20 magazines in the United States that had sections for swinging.

Is swinging an international phenomenon?

Swingers have become a real community organization (such as birth and ISU) and branches spread all over the world. If you're in a foreign country and want to make contact with other swingers, there are handy guides with localization of clubs.

For a stay, you can call an agency that offers a complete package for fun. Tenders are countless, with special accommodation offers for those into the swinglifestyle, plus transport companies and even aviation.

What are the types of swinging?

There are three different types:

• Soft swinging: They exchange partners, but couples remain in the same room. Not acceptable penetration. It is instead touching, kissing and even oral sex.
• Closed swinging: They exchange partners, but the newly formed couples have sex in different rooms.
• Open swinging: They change partners and have sex in the same room. Most often in group sex, resulting in an orgy.

How do you classify swinger parties?

• Parties "off-premise": These swinger parties will have sex elsewhere.
• Parties "on-premise": To these parties, sex is expected to take place between participants.

Swinging is an alternative to a monogamous relationship. It is a way to add spice to a relationship. However, sometimes the experience is a little too spicy.

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Mike Hatcher writes about open relationships, swinging and sex, and relationship advice for alternative sex lives.