Hundreds of thousands of people are missing around the world as a result of armed conflict, other situations of violence, disasters and in the context of migration. In many cases, efforts to address such case-loads fall outside the mandates, or exceed the capacity, of existing national institutions. It is in this con-text that consideration should be given to setting up a dedicated national mechanism on the missing, with the aim of clarifying the fate and whereabouts of missing persons and providing support to their families. Drawing on experiences in a diverse range of contexts around the world, this document provides guidance on subjects such as the underlying legal framework and mandates of mechanisms, the role and needs of families of missing persons, the importance of political will, and the management and protection of relevant data.