Intra-EU mobility has become increasingly important over the past years. While there are no legal barriers preventing young intra-EU migrants from studying or working in another EU country, many of them face obstacles with respect to their integration into the destination country. Likewise, those who return to their origin countries after having spent some time abroad are also often confronted with diverse challenges. Support measures provided by the EU or national governments and by civil society organisations play an important role in overcoming those obstacles, which might not always match with migrants and returnees needs. Drawing on the outcomes of the collaborative project YMOBILITY, which investigated the relationship between young-peoples transition from youth to adulthood and their mobility between EU Member States from an international and interdisciplinary perspective, three general findings can be highlighted. First, (re)integration support should include language training and labour market integration measures, but also address other aspects, such as access to housing and cultural integration. Most importantly, efficient support measures need to be tailored to the particular needs of young intra-EU migrants and returnees. Second, support in integration that targets to overcome acculturation issues in the sphere of everyday life is generally offered by civil society, including organisations created by and for migrants and returnees. However, these organisations tend to be underfunded and understaffed, because they are often based on voluntary work, leading to a limited scope and the underuse of their potential. Third, a large group of migrants and returnees are unaware of, or unwilling to use, social support measures, indicating the particular need to provide measures that improve the communication between providers of support and migrants and returnees.