Almost half the global population is under the age of 30, and the relation between new forms of societal participation and “political apathy”, in the sense of decreasing turnout in elections, is the subject of vivid debates. Nevertheless, “youth” is not at the centre of political decision-making and young people are underrepresented in formal institutions. Most recently, however, the international community stepped up their efforts in engaging with young people when it comes to those decision-making processes, which affect the living environment of youth.This thesis firstly examines the various concepts of and approaches to youth participation, including a human rights approach, its areas, mechanisms and levels. Thereby, so-called ladder models will be assessed and later on applied to the specific participation processes of selected international and regional organisations. Likewise, the United Nations, the Council of Europes, the European Unions and the Organisation for Security and Co-operation in Europes youth policy development and their respective actors will be scrutinised in order to answer the following questions:- What is the added value of youth participation? - Is there an international or European standard of youth policy?- What are the instruments of youth participation in regional and universal organisations?- How effective and genuinely participatory are these instruments?- To which extent are the engaged youth individuals representative and legitimated?- Which instruments and which organisations offer best opportunities for participation? After balancing immanent opportunities and challenges, and reviewing inter-institutional partnerships, the thesis gives recommendations for youth-mainstreaming and for furthering cross-sectoral youth participation.