As members of the Institute of Biology, you may often have been asked at dinners or parties whether you think GM crops and food are safe, desirable or part of a capitalist conspiracy. Of course, your answer to this will depend on many personal factors but at least this book will give you some of the factual information on which to base your views. It is refreshingly free from efforts to convert.

The eight multi-authored chapters result from a meeting of the Cambridge Society for the Application of Research held in March 2002 and represent views from scientists involved in government regulatory processes, commerce, ecology and with an interest in the Third World. The first generation of transgenic plants were designed to make it easier for agriculturalists to grow them. Genes have been inserted which make the plants tolerant to herbicides such as glyphosate (Roundup) by exploiting biosynthetic pathways which differ in plants and bacteria. By putting genes for the bacterial pathways into the crops, they become resistant while the weeds remain sensitive. When genes for an insecticidal protein from Bacillus thuringiensis are introduced into crops an in-built protection from pest damage is provided.

The second generation products, still largely in development, are intended to benefit the consumer or the manufacturer of food products from the crops. Crops may be developed which can be stored longer, able to grow in changing climate conditions associated with global warming or with altered nutritional values which may reduce unhealthy precursors which predispose to diseases such as heart disease or cancer. Most excitingly GM 'yellow rice' is being developed in which three genes for the biosynthesis of beta carotene have been introduced into a regular rice strain. The hope is that this will be used to produce a Vitamin A precursor which can be used to treat a serious nutrient deficiency causing blindness in the third world.

The arguments for and against are many and varied and it is important to remember, as all the authors point out, that we already have a great deal of experience because GM crops have been widely grown and eaten in many countries, particulary but not exclusively the USA, for several years now. Worldwide GM crops now cover an area equal to about 14 times the cropped area of Great Britain. In 2001 20% of the world's cotton came from insect resistant GM varieties. Several studies on cotton have already appeared and not only have yields gone up but there has been a reduction in pesticide related sickness, not to mention an easier life for peasant farmers. On the other hand it is perceived are that there may be risks to health from eating the crops, there may be risks from transferring genes into other varieties or that the ecosystem may be altered by changes in crop management. The organic farming movement in particular has a zero tolerance approach to any form of GM crop which may in any way contamintate its plants or its fields.

The level of government scrutiny is impressive. Clearly experts from many fields are involved and every year each member of the Advisory Committee on Releases to the Environment receives documents for comment that form a pile over 1.5 metres high. However, at the end of the day, as most of the authors point out, industry will only produce what the consumer will purchase and their stated attitudes often don't concide with what the contents of the shopping basket show. At the moment most consumers feel that there are no obvious benefits to them personally from the technology.

The arguments in both directions are presented clearly and fairly throughout the book but I was influenced by Sir Brian Heap's final chapter. He points out that in order to produce the vast extra supply of food needed to feed the world's increasing population and our ever increasing expectations, over the last 50 years we have lost one fifth of world's topsoil, a fifth of its agricultural land and a third of its forests. He asks whether if the new technologies may help safeguard the environment, improve the lot of the farmer and the disadvantaged then the consequences of not introducing them may be the most serious of all.

This book should help you make up your own mind about the best way forward.