How many times have you been in some exotic part of the world and, caught up in the euphoria of the moment, looked at a guide leading a group on the sort of adventure that you enjoy and thought, 'I would love to do that job'? By comparison to their apparently carefree, action-packed, outdoor existence, your office job appears mundane, depressingly unadventurous and lacking any form of excitement. At that moment, the thought of waking up on the banks of the Zambesi or in a remote camp on the Annapurna circuit, and of spending your days battling your raft-full of excited clients down raging rapids or trekking in the shadow of the Himalayas appears far more romantic than the concept of leaving your home to fight with the commuter crush on the way to a desk full of flickering computer screens and ringing telephones. But before you fire off a letter of resignation to your managing director and shower an unsuspecting adventure tourism industry with your newly rewritten CV, it may be worth considering some of the practicalities.

To begin with, you should ask yourself what it is about foreign travel and adventure holidays that you enjoy so much. Apart from the more obvious pleasures, do you associate travelling with being free from all responsibilities, away from the pressures of deadlines and demanding clients? Is it about being able to take every day as it comes, moving on at whim, without a care in the world, not needing to answer to others? Is it about pushing yourself on challenges that take you towards your physical limits? Is travelling in the comforting knowledge that your secure job will ensure that your mortgage and all other bills are paid a subliminal part of your enjoyment? If any of these scenarios strike a chord, you have some hard truths to confront before putting the stamp on that resignation letter.

First of all, you may as well recognise that no one ever got rich from guiding. It is a lifestyle choice that has little, if anything, to do with paying mortgages or saving a nest egg for your retirement. Rates of pay are low, in many cases amounting to your keep plus a small amount of pocket money. Many companies get enough staff purely by giving them a free trip, and in some cases companies expect staff not only to work for them but also to pay a contribution towards their expenses for the privilege of doing so.

Secondly, working as a guide or tour leader requires an extremely high level of commitment. You are on call 24 hours per day and take on considerable responsibility for your the safety of your clients, as well as their wellbeing and enjoyment. In addition to any specialist technical skills, such as mountain leadership or kayaking experience, guides often need to be able to act as group motivator, administrator, cook, driver, mechanic, equipment repairer, camp manager, medic, social worker and agony aunt. Every problem, from the most serious to the most trivial, will find its way straight to your tent door.

One company with a regular requirement for tour leaders is Encounter Overland, which employs around 20 leaders at any one time. The leaders normally work alone, driving groups of up to 24 clients of mixed nationality on itineraries lasting between two and 32 weeks through Africa, Asia and South America. Leaders may be deployed for up to 18 months at a time. They are on the road for roughly nine months of a year, with most of the remainder of the time dedicated to the maintenance of their vehicles.

Welikanna reckons that she can normally spot the qualities that she is looking for in a leader within five minutes of meeting someone. "During a recruitment drive we probably take three out of every 100 who apply, but those who come to us independently tend to be more motivated and we may take on 30 per cent of those who do so."

Those that are taken on are put through a six-month training programme in the UK, which concentrates mainly on learning to drive, repair and maintain the company's vehicles (potential leaders must obtain their passenger carrying vehicle driving licence at their own expense). They also do some first aid training, learn how to recognise tropical diseases and spend three weeks in the London office to meet the staff and see the UK end of the business, dealing with clients, obtaining visas, organising airport runs and seeing how crises are handled. On completion of the training a leader/driver spends up to four months apprenticed to an experienced leader in the field in either Africa or Asia before leading their own trips.

Encounter Overland's leaders work for the company for an average of four years. "If new leaders are going to have problems," says Welikanna, "it will normally be difficulty in handling the groups or simply not having the stamina to cope with living in close proximity to 24 people for whom they are responsible, operating on an average of five hours sleep per night."

The emphasis on people skills for group leaders is reiterated by Mark Hannaford, managing director of Across the Divide, a company specialising in mounting treks and cycle rides in remote parts of the world. "Our staff need to have a high level of experience in outdoor education and skills, but the job is mainly about being able to fit into the team and work well with clients. The core values that we look for in our staff are maturity, loyalty, integrity, dependability, good communication skills with people of all ages and backgrounds and the ability to remain calm in a crisis and manage a situation effectively until other help arrives. We tend to have people who are well travelled and have a broad view of the world. It is important that everyone is fit and able to carry heavy loads - and a good sense of humour is essential."

Across the Divide mounts expeditions of between 30 and 100 clients, and operates in the field for a week to ten days, deploying staff in teams under the guidance of an expedition leader. Group leaders are responsible for up to 20 clients on a daily basis, working together with a local guide. Expedition doctors provide routine and emergency care for up to 50 people, normally with the support of a nurse or paramedic. Doctors are required to have recent accident and emergency department experience and need to be able to operate in field conditions without the level of back-up to which those used to working in hospital will be accustomed.

Managing large groups in remote areas requires special skills and operating procedures. Across the Divide uses radios and satellite telephones to keep groups in close contact with each other and to facilitate overall control by the expedition leader.

Each company in the adventure travel field has its own individual style of operating. Some guides enjoy the autonomy of working on their own, whilst others prefer the camaraderie and support of working in a close-knit team. It is extremely important to identify exactly how you will be expected to operate - only work in situations which you feel comfortable with. Dealing with exercise casualties on training courses is excellent practice, but it is a very different matter when you are leading a group on your own and you become faced with a real situation involving a traumatic injury and a group of novices who are frightened by what they have seen when help is a long way away.

Although many companies stress the importance of people skills, that does not in any way diminish the need for technical skills and qualifications. Companies looking for trekking, mountaineering, canoeing or diving guides, for example, will normally specify minimum standards of qualifications from the appropriate British authority such as the Mountain Leader Training Board or the British Sub Aqua Club. In addition, first aid qualifications or validated training will not only make you much more attractive to an employer but give you a great deal of confidence on the ground.

I am constantly amazed by the number of clients who come on arduous adventure trips to remote areas of the world with serious medical conditions that they fail to mention until they find themselves in difficulty. Diabetics, on the whole, are perfectly capable of maintaining their insulin levels, but it as well to know what to do just in case. Of more concern are those who turn out to have a history of epilepsy, heart conditions, psychiatric problems or, as in one recent instance, a difficult pregnancy. Expedition medicine can involve much more than treating blisters, strapping sore knees and issuing the odd sachet of Immodium, and all of this comes on top of the many other claims on a guide's time.

The life of a tour leader is often far from the glamorous, carefree existence that it may appear to be at first glance. Working in remote areas of Third World countries often means that the kinds of support systems that we take for granted at home, from garages and hospitals to something as elementary as restaurants where the food is safe to eat, are no longer there. Clients can be unreasonably demanding, utterly frustrating and have a habit of doing the worst possible thing at the most inconvenient moment. As a tour leader you must guide well within your own technical and physical capabilities so that you always have reserves of expertise, strength and stamina to give your clients when they need assistance. By definition, this means that the trips that you lead for commercial organisations may well be fulfilling in a leadership sense, but they are unlikely to satisfy any personal cravings for a physical challenge that will stretch you.

The rewards, however, justify all of the hassle. I never cease to get a thrill from working in areas of great natural beauty. There is a special satisfaction derived from enabling people to realise their dreams or aspirations, whether that involves showing them a part of the world they have never seen before or helping them to complete a physical challenge. For many clients an expedition is truly the experience of a lifetime, one that leaves them profoundly moved. At the end of a trek across the Namib Desert recently, one of my group, a young 18-stone cockney pipe-lagger, burst into tears. "John," he sobbed, "you cannot begin to understand what this means to me. Where I come from in the East End of London, the Namib Desert is unimaginable. It might as well be on Mars - and I have walked the whole way across it." The fact that he had been the joker of the party throughout the trek made his reaction all the more poignant.

If you do decide to post that letter of resignation and look for a job as a tour leader, it is worth looking at the classified section of the various outdoor and adventure travel magazines for companies advertising for staff. The Expedition Advisory Centre at the Royal Geographical Society maintains a register of personnel available for expeditions, with CVs for each person, and also publishes a bulletin of expeditions looking for people with particular skills. Some commercial companies do access the register of personnel when looking for staff, but it is more likely to produce positions on private adventures or scientific expeditions.

Finally, it is beholden to all tour leaders to remember that they bear a responsibility not only to their clients and the organisations that they work for, but to the peoples and places that they visit. Part of doing so is to ensure that you are in a position, through a combination of experience and research, to pass on as much information about the country that you are visiting as you can to assist your clients' ability to enjoy and understand the environment that they are in. It is up to a tour leader to set a standard for group behaviour and attitudes. Groups sometimes need to be educated to respect local cultures, act in a way that is mindful of the sensitivities of the people whom they meet and at all times minimise their impact on the environment through good camp-craft and trail discipline.