Heart Searching: Let your head rule your heart: David Marsh concludes our series on the downside of dating agencies with some advice on finding one you can trust

The vast majority of introduction agencies are reputable organisations run by honest businessmen and women who genuinely want to bring people together, turning lonely singles into happy couples.

That may seem a surprising conclusion to anyone who has been following this page closely over the past few weeks, as we have presented a sorry tale of people who have suffered financially and emotionally by paying to join an agency, only to be sadly disappointed by being matched with totally unsuitable partners - and, in some cases, with no one at all.

The good news is that, after more than a year of editing this page, I feel quite confident in reassuring people that such cases are the exception rather than the rule. But how can you be sure that you have found one you can really trust with your cash - and your love life?

Penrose Halson, who with her husband Bill, runs the highly respected Katharine Allen Marriage Bureau and the Society of Marriage Bureaux, says: 'Sadly, it is still possible for the disreputable to advertise and thrive, and for gullible people to suffer.

'Instead of offering hope and the possibility of a happy relationship, they provide danger, disillusion, fear and loss of money. Bad agencies prey on people in the knowledge that distressed clients seldom complain. Because, sadly, there is still some stigma about using an agency to meet people, many clients do not like their connection with an agency to be known. So if they are cheated they tend to keep quiet.'

She continues: 'If people did more homework before joining an introduction agency, unscrupulous organisations would find it much harder to survive. They should join only well-established agencies which belong to a self- regulating body, advertise in respectable publications, interview their clients, adhere to a sensible code of conduct, employ pleasant staff, make their objectives, terms and conditions totally clear, and provide a proper contract. Danger signs are glowing promises and high-pressure sales techniques.'

Apart from the Society of Marriage Bureaux, whose rules are so strict that currently only one bureau - Katharine Allen - qualifies for membership, the other self- regulating body is the Association of British Introduction Agencies (ABIA), set up after the Office of Fair Trading recommended the voluntary formation of a trade association which should draw up a code of practice.

As well as a code for its members, ABIA publishes a list of do's and don'ts of joining an agency. The do's include asking how many introductions you can reasonably expect to be given, and maintaining regular contact with the agency you choose. The don'ts include not joining an agency that uses a post office box number or premium rate telephone number, and never parting with a membership fee without having been given the opportunity to visit the agency concerned.

Frances Pyne, the association's press officer, also warns of what she calls 'timeshare selling techniques' employed by some agencies - not being upfront about costs, not giving you time to consider what you are doing, and other hard-sell tactics.

Another useful ABIA list provides a guide of do's and don'ts for that first meeting. This includes sensible advice such as telling a friend the name of the person you are meeting, where you are meeting them, and when to expect you back. Among the don'ts are don't commit yourself to a long first date in case you don't get on with the other person, don't pretend to be something you're not - and don't get drunk]

The ABIA will supply you with a list of its 30 or so members. There are plenty of good agencies that do not belong to the association - indeed, some have specifically decided that they do not wish to join. However, many people undoubtedly find it reassuring that, in an industry that is not licensed or regulated by any outside body, there is some self-regulation.

Mary Balfour, an ABIA council member who runs the successful upmarket agency Drawing Down the Moon, suggests 'nine golden rules' on how to choose an agency: check if it belongs to the ABIA, covers your geographical area, has members in the appropriate age group, has an acceptable ratio of men and women, has members of a similar social and educational background to your own, advertises in media you approve of, has enough staff, allows you to choose your potential partners, and runs social events as well as one-to-one introductions.

From my own experience in this area, I would add the following personal rules of thumb about agencies' charges:

First, don't have anything to do with an agency that will not tell you over the telephone what it costs to join. Some will try to tell you that they offer a personal service tailored to your particular needs, and that therefore the costs vary. This is rubbish. What it means is that they will charge you as much as they think you will be prepared to pay.

Second, think very carefully indeed about how much you actually do pay. At the upmarket end of the business, there are good agencies providing an excellent personal service for around pounds 500 to pounds 600. If someone tries to charge you pounds 1,000 or even more, what are they doing for the money? It is, frankly, very difficult to imagine how such fees can possibly be justified.

Finally, you could do a lot worse than follow Penrose Halson's advice to read Linda Sonntag's book Finding the Love of Your Life (reviewed here last year), and read what Mrs Halson describes as the 'invaluable' Heart Searching page in the Independent.

ABIA: 25 Abingdon Road, London W8 6AH (071-937 2800)

Society of Marriage Bureaux: 1 Mandeville Place, London W1M 5LB (071-935 6408)