As Confucius said, a journey of a thousand miles begins with a single step - deciding to become a volunteer is the most important step in making a positive difference somewhere in the world. Volunteering has developed into a huge international industry and there numerous organisations that can fix you up with a placement, even if you've never been abroad before. However, you must be prepared to pay most of your own expenses - development and conservation projects rely heavily on paying volunteers.

Many projects are open to people with no previous experience, but there's more to volunteering than just turning up with a spade and asking where to dig. Most organisations want you to commit a minimum length of time and you'll be expected to put in long days working in challenging and unfamiliar surroundings. Living conditions can be basic, without running water or electricity - understandably, not every would-be volunteer has what it takes.

Volunteers are needed all over the world but people who turn up unannounced are not welcome. Charities and NGOs (Non-Governmental Organisations) are looking for volunteers with specific skills for specific jobs and most organisations obtain their volunteers through sending agencies in Europe, Australia, New Zealand and the USA. These organisations work a little like temping agencies, matching volunteers to projects that need their specific skills and experience. Agencies tend to specialise in either conservation or development and humanitarian work, but year-out organisations like i-to-i and Teaching & Projects Abroad offer both kinds of placement.

Don't panic if you don't have first-hand experience - there are plenty of projects that accept complete new-comers to development or conservation. Many day to day business skills transfer easily into voluntary work and there are also openings at the front line of humanitarian relief for volunteers with professional skills, particularly doctors and nurses.

Most organisations have a minimum age of 17 or 18 and take volunteers up to 65 or 70, but you may have to take a medical to show you are healthy enough for the work. Some projects also have specific skills requirements - eg a TEFL certificate for teaching placements or a medical qualification to work in a clinic - but conservation projects are generally open to anyone. If you want to volunteer with children, you may have to take a criminal record check.

You can volunteer for as little as a week or as much as two years, depending on the project, and some projects will let you extend your stay once you arrive. Accommodation is often fairly basic - volunteers often stay with host families or in expedition camps - and you must cook for yourself or share communal meals with local people. Consider the living arrangements when you pack and remember to get all the necessary travel jabs and anti-malarial drugs.

To cut down on unnecessary paperwork, almost all sending agencies recommend that volunteers work on a tourist visa. Sending agencies usually accept people of all nationalities, as long as you can get a tourist visa for the country where you want to volunteer. If you are volunteering long-term, the sending organisation may sponsor you on a formal work or volunteer visa.

Most sending agencies have a formal selection process and you must demonstrate that you have the ability to adjust to new situations and work as part of a team. Agencies are also looking for enthusiasm and commitment. You should call or visit the website for an application form to start off the process. Once you've filled in the paperwork and paid a registration fee or deposit, there will be an interview, either by telephone or in person. This is often followed by a group exercise or team building weekend which will allow the organisation to see how you interact with other people.

The fees charged by the different agencies vary widely - you can pay as little as £100 with a grassroots agency or as much as £4000 with one of the big year-out organisations. This covers meals, accommodation, project costs and local transport, but flights, visas and travel insurance are almost always extra and you will have to provide money for incidental expenses like evenings out and excursions away from the project. Most organisations require participants to have adequate health insurance.

If you would rather make your own arrangements, there are numerous websites that provide listings of volunteering opportunities worldwide and most have a searchable database so you can search for projects in a particular region or field.

Once you find a project, you can apply directly to the host organisation, avoiding the fees charged by sending agencies. However, you will still have to cover your own transport costs and you may also have to make a financial contribution to the running of the project. If you go directly to a charity or NGO, you will also miss out on the support network of going through an established sending organisation, so you need to be highly motived and self-reliant to go down this route.

Whether you apply directly to an NGO or go through a sending agency, you should begin the application process well in advance of when you want to start. Some projects accept volunteers on a continuous basis, others require you to start on fixed dates - as a general rule, you should apply at least three months early for a year-out organisation and up to a year in advance for an executive volunteering programme such as VSO or the Peace Corps.

Chooosing a Volunteer Organisation

• What does the organisation do and how is it funded?
• Are placements arranged directly through the organisation or does it act as a sending agency?
• Who can volunteer with the company and how are volunteers selected?
• When is the deadline for applications and is there a deposit to secure a place (if so, is this refundable)?
• What will I be doing on the project and how will this benefit local people?
• What skills are needed and how do volunteers benefit from taking part?
• Where are the placements and how long do placements last?
• Can volunteers choose where to go?
• Can volunteers extend the placement after they arrive or visit more than one place?
• How much does the placement cost and what is included (eg flights, visas, insurance, meals, accommodation...)?
• Is insurance included? If not, make sure you take out sufficient travel insurance before you leave.
• Is any training provided (this may take the form of an orientation programme before you leave or after you arrive in the country)?
• What happens if things go wrong? Is there a local representative or emergency number you can call to provide assistance in an emergency? Is medical care available?
• Do volunteers work in groups or alone? Will other volunteers be living nearby?
• What are the living arrangements? Do volunteers share rooms or stay with local families? Are meals provided?
• Is it possible to volunteer with a friend or partner?
• How can volunteers keep in touch with friends and family?
• Is any support provided when volunteers return home?