The world can be your oyster...

That was the moment that the teacher (I confess, it was me) realised the skills needed to teach English as a foreign language. It's not as easy as it might appear, and you have to be properly trained if you want a job with a reputable employer. But if you do take a recognised qualification, then a whole new world opens up, providing plenty of opportunity for travel, and even the chance to set up your own business.

Take 62-year-old Jenny Lawson, for example. She began as an untrained English teacher at a Chinese private school in Sarawak, where her Army husband was posted. When the couple later retired to France, she decided to get a proper qualification and applied for a course in London. She was then 50, without a degree, and says that the course was very intensive. But Lawson is now a successful private English teacher in France.

Whatever sort of job you have in mind, ideally, you need a Tefl qualification. Make sure the course is externally validated by a recognised exam board or university. It should be at least 100 hours long, and include supervised and assessed teaching practice (usually around six hours).

Tefl (Teaching English as a Foreign Language - nothing to do with non-stick frying pans) and Tesol (Teaching English to Speakers of Other Languages) basically mean the same thing. The best-known qualifications are the Cambridge Celta and the Trinity College Tesol Certificate, both offered at centres in the UK and overseas. There are many other reputable courses - see www.quality-tesol-ed.org.uk - as well as introductory courses that could help you to decide whether Tefl is for you.

Cactus Tefl (www.cactustefl.com) offers advice for prospective teachers, with information on courses and how to find work. It features a number of satisfied teachers on its website, such as Jane Rogers, who teaches in Barcelona. She finished university last year and was "desperate to work abroad. I thought teaching would be the ideal way to experience other cultures". Agnes Marton, meanwhile, is now teaching in Hungary, after finishing a Celta course in Budapest. Her students include a six-year-old boy and a group of bankers who need business English.

Saxoncourt, a recruitment agency, places 600 teachers in private language schools in 20 countries every year. Paul Mitchell, speaking for the company, says that it mainly recruits for employers in Italy and Spain who want people with a Tefl qualification and at least a year's post-Tefl teaching experience.

To get on to a recognised course you need at least two A-levels, and, in some cases, a first degree, and to be aged 18 or over. The cost of a full- time course is between £750-£1,000. Some Tefl courses are offered through distance learning, which is far cheaper at £250-£400. But teaching observation and practice, essential to most employers, are not always part of the course.

Once qualified, the next step is to find work. Many overseas employers advertise posts online, while the British Council has job opportunities on its website (www.britishcouncil.org). If you know where you want to work, consider getting the qualification locally, as this may make it easier to find your first job. Jenny Lawson says that language schools in France are always looking for Tefl teachers. However, she chooses to work privately as some city schools have problems with poor pay, large classes and issues of discipline.

Her advice to those considering doing a Tefl course and working in Europe is to be aware of the reality of the job. "The hours can be anti-social, with many evening classes. You'll never be rich, and, as with all new projects, things begin slowly and it can take years to become established. And it's great having long holidays but, alas, they are unpaid!"