Cancer Incidence in Five Continents (CI5) is the result of a long collaboration between the International Agency for Research on Cancer and the International Association of Cancer Registries. The publications provide data on cancer incidence collected by population-based cancer registries over more than fifty years, and the contents of this collected edition represent the results of this effort. Their work deserves gratitude not only from investigators who use the information they provide, but also from all those who may benefit from the increase in our knowledge of cancer patterns and trends. Particular thanks are due to those cancer registries who agreed to make their results available through CI5plus, a level of detail not hitherto possible in the printed volumes.

We would like to recognize and acknowledge also the work of the 34 editors who were involved in collecting, evaluating and preparing the data appearing in one or more of the eleven volumes of CI5. Particular thanks are due to the late Sir Richard Doll, who was in large measure responsible for bringing to fruition the idea of creating a source of comparable international data on cancer incidence for the purposes of research into cancer cause and prevention.

The authors would like to thank Dr Fidler and Dr Pilleron at IARC for their careful check of the data.