Youth mainstreaming involves the integration of a youth perspective into the preparation, design, implementation, monitoring and evaluation of all policies and programmes that concern and affect young people. Youth mainstreaming also aims to shape institutional and policymaking processes that provide space and opportunities for young people to have a say in the decisions that affect them. At the European Union level, youth mainstreaming has its roots in the 2001 White Paper on a new impetus for European youth (European Commission, 2001), which laid the foundations for European governance in the youth field. More than two decades later, mainstreaming youth and youth participation are foundational principles of the 2019-2027 EU Youth Strategy, which -- supported by instruments such as the EU youth dialogue and EU youth programmes (Erasmus+ youth in action and the EU Solidarity Corps) -- highlights that 'only by mainstreaming youth as a priority amongst different policy areas it can be ensured that the specific needs or effects for young people in envisaged policies or programs are taken into account. To lead by example, at EU level a cross-sectoral approach should be further pursued as a fundamental basis. Furthermore, youth mainstreaming can only be effective when it also guarantees a say for young people in all possible policy areas that affect them' (Council of the European Union, 2018).