these pages contain a number of chapters from specialists in the field who consider, from a number of different perspectives, the currently available evidence that supports the environmental cancer aetiology hypothesis. this constitutes the first part of the book. in the second part of the book, an examination of the policy implications of accepting that the cancer epidemic may essentially be preventable is presented. this will pose some difficult problems for politicians and decision-makers, who will have to consider adopting policies that may damage the economy in the short term in order to reap health benefits which will only become apparent several decades in the future.