At the beginning of 2006 the media reported instances where people who had been convicted of sexual offences against children were permitted to work in schools. A list of unsuitable people (known as ‘List 99’) has existed for over 80 years and yet the system appears to have broken down. In this article I seek to examine some of the issues involved in the operation of List 99, including the suggestion that those who are cautioned for committing offences against children should equally be unable to work with children. A second article will then critically analyse the changes proposed by the government to the operation of List 99 and the vetting of those who wish to work with children.