Ethical principles to be followed in cancer screening programmes are intended mainly to minimize unnecessary harm for the participating individuals. The principles that have been recommended by the Council of Europe, Committee of Ministers are: 1) Effectiveness is a necessary prerequisite for a screening activity to be ethical. 2) The need for a balance between the advantages and disadvantages of screening for a target population and an individual, between social and economic costs, equity and individual rights and freedoms. 3) The need for information about both the positive and the negative aspects of a screening programme. 4) The decision to participate in a screening programme or in research should be taken freely. 5) The right to integrity, i.e., the results of the tests are not communicated to those who do not wish to be informed, and the need to have laws and regulations on any communication of personal data derived from screening to third parties.