Illegal logging is big business. It is said to affect over 70 countries - in many, over half the harvest is thought to be illegal - and the environmental devastation it causes is often plain to see. Yet we know surprisingly little about the real extent of illegal logging and its underlying causes.

Illegal logging: Law Enforcement, Livelihoods and the Timber Trade provides a comprehensive analysis of what we know - and don't know - about illegal logging. "If we fail to understand and address the underlying causes of illegal logging, then there is little chance of reducing the trade in illegal timber," explains the editor, Luca Tacconi, formerly of CIFOR and now with the Australian National University in Canberra. Drawing on research from across the world, the book examines the various factors which encourage companies, communities and individuals to illegally harvest and trade timber. The high demand for timber, and the willingness of governments to turn a blind eye to illegal timber harvesting, are obvious drivers. Inconsistent laws, poverty and corruption are among the others discussed here.

There is a surprising lack of reliable data about the scale and nature of illegal logging. Illegal logging can mean many different things, from major infractions such as commercial-scale exploitation in protected areas to relatively minor wrongdoing - for example, failing to provide the right paperwork for the transportation of logs from legitimate concessions. Yet all too often studies have lumped together a multitude of different infractions. "This means that comparisons between different countries, or even different areas within the same country, are often hard or impossible to make," says Tacconi.

Illegal logging is generally portrayed in entirely negative terms, but the authors suggest that this is too simplistic a view. Illegal logging often provides an income - albeit a meagre one - for rural communities. Unfortunately, and unfairly, they tend to be the ones who suffer most from operations designed to suppress illegal logging. "If you look at what's happened in Kalimantan," explains CIFOR researcher Krystof Obidzinski, "the 'sweeping operations' run by the Indonesian military have hurt local communities most, and hardly affected the cukong who control the illegal logging trade." Matters are simply made worse, in Indonesia and many other countries, by the existence of laws that are biased against the rural poor.

The book suggests that projects designed to reduce the illegal logging will not lead to substantial changes unless governments are genuinely committed to tackling the problem. Many are not, says Tacconi, although exceptions do exist. Bolivia, for example, has implemented reforms to allow poorer, marginalised groups legal access to forestry resources, thereby legitimising benign, through previously illegal, activities. Other countries need to follow suit, and regulatory frameworks governing forestry activities need to be reformed to remove the bias against rural communities.

In Indonesia, the disparity between supply and demand is driving illegal logging, and this is one of the reasons why the government has recently announced an ambitious programme to plant over 9 million hectares of trees on degraded land by 2016. "It's absolutely vital that this succeeds if the country is to have any hope of creating a sustainable future for its forests," says Obidzinski. "If it doesn't succeed, illegal logging will continue to be a major problem." He believes that the success of the programme will hinge on the degree to which it involves local communities. If they can benefit from planting and harvesting trees, then the incentive to log illegally in natural forests will be much reduced.

Tacconi says that although he is sceptical about the commitment of many governments to stop illegal logging, the lure of hard cash could make a difference. If developed countries pay developing countries to conserve their forests, and thus reduce carbon emissions, it could bring about a significant change in behaviour. "Some think that illegal logging poses a threat to the implementation of the activities aimed at avoiding deforestation and degradation, proposed within the United Nations Framework Convention on Climate Change," says Tacconi, "but we could find that those activities actually provide incentives to governments and the private sector to control illegal logging."

If developed countries pay developing countries to conserve their forests, and thus reduce carbon emissions, it could bring about a significant change in behaviour.