This paper critically reviews the current state of knowledge about undocumented migration and
irregular employment in South Africa as a baseline exercise. It begins with an overview of the major causes of the upsurge in migration to South Africa from neighbouring countries. The paper then examines how the current policy framework impacts upon definitions of irregular employment and undocumented migration. The next section of the paper looks at various attempts to provide defensible general numbers of the volume of authorized and unauthorized migrants in the country. This leads into a discussion of the need for a more refined and disaggregated understanding of migration and employment. Finally, the irregular employment matrix developed for the recent ILO/IOM Symposium in the Hague is used to disaggregate the different forms of migration and irregularity in South Africa.