Defence procurement is the process through which authorities in the field of defence and security acquire various goods, services or works they need in order to perform their duties and missions. Defence procurement constitutes a noticeable segment of public procurement in the European Union. SIGMA Brief 23 gives a short overview of the particular characteristics of defence procurement and how defence procurement is organised in the European Union. It also gives an overview of the regulatory framework of the European Union with special attention to the Defence and Security Directive (2009/81/EC). The Brief also covers some other linking issues such as offsets and parallel regimes (defence procurement between the European Union and third countries).