www.companions2travel.co.uk launched in July 2004 and has nearly 8,000 members, who pay £25 per year to be matched with holiday companions with the same interests and holiday preferences. Rivals, Someone2travelwith.com is set for official launch in February 2006, and offers free membership but charges £30 when a match with a potential companion is accepted by both parties (with nine further free "matches").

With around a sixth of British adults now living alone - a statistic set to increase - the websites are keen to cash-in on a burgeoning market of travellers who are looking for companions, although both want to make it clear they are not dating agencies. "We don't want anyone to feel that they are obliged to be any more than a travel companion," the Companions2travel.co.uk site tells it users.

Single travellers aren't always looking for love, says Someone2travelwith.com founder Diane Denney. "They're not sad and lonely," she told Times Online, "and they don't want a dating agency, they just want companions." Her members have various reasons for wanting a travel companion, she says, including a spouse or partner who doesn't share similar interests, or the desire to travel in numbers due to safety concerns.

But travelling with a stranger raises safety concerns of its own. Consequently, both websites come with weighty security statements and encourage members to converse only through the secure and private site messaging services that do not disclose personal details.

Denney says: "We trust people to use their own instincts to decide whether or not to pursue a match. The exchange of information should be mutual, and we warn members to be suspicious if it's one-sided." Her website also carries extensive safety information, much of it from the Suzy Lamplugh Trust, a charity dedicated to personal safety.

Anne Williams, a 50-year old civil servant from Wetherby is typical of the membership of Companions2travel.co.uk, who "fell between the 18-30 and guided holidays for older people". While safety was a concern for Anne, she said the anonymity of the messaging service was a plus, and she had no qualms about spending a long weekend in Barcelona with four other members.

The group, comprising a man in his 60s, a divorced Mum and two married men whose wives don't enjoy travelling, all stayed in single rooms. The trip was a success and Anne is now looking for companions for a holiday in the Greek islands and an autumn trip to New England.

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