This article explores the issue of missing from and missing out on education. It argues that too little is known with regard to the characteristics of children and young people missing from schooling. It postulates that many of these pupils will have social, emotional and behavioural difficulties which are largely unrecognized and thus not provided for. The number of missing children and young people is estimated at 100,000 and evidence is provided to support this. Literature is drawn upon which illustrates ways in which it is possible to go missing despite recent attempts by agencies to tighten recording systems. The cost to society from having pupils missing from education is briefly explored. The article concludes that the notion of a "knot worker" is one that should be pursued if the number of missing pupils is to be effectively reduced.