Prof Lambin talks about the heterogeneity of tumours and the fact that some areas of tumours are more therapy resistant. He has been involved in testing new imaging modalities in order to improve the accuracy of localizing these areas in the hope that the radiation dose can be increased to just these sections. Prof Lambin discusses the problem of making sure that drugs are reaching all areas of the tumour, something that can only be achieved with the co-operation between radiation oncologists and medical oncologists. He concludes with news of a new trial on non-small cell lung cancer which is still to be completed but which could be a powerful way of controlling disease by using radiation in a more intelligent way.