This resource is a practical booklet exploring the concept and implementation of reinforced mentorship in European Solidarity Corps projects. Reinforced mentorship is presented as an intensified mentoring approach designed to provide stronger and more frequent guidance for volunteers who face additional barriers to participation. The publication combines conceptual explanations, research insights and practical recommendations drawn from the experience of organisations working with volunteers with diverse abilities. It is structured into several sections that guide readers through both the rationale and the implementation of reinforced mentorship. The first section introduces the concept of reinforced mentorship and explains why additional mentoring support is sometimes necessary for volunteers with fewer opportunities. It also presents the results of a survey conducted among European Solidarity Corps organisations, which collected experiences from practitioners working with volunteers facing barriers such as mental health challenges, disabilities, socio-economic difficulties or language barriers. The second section provides good practice examples for mentoring volunteers from different groups who may face hidden or visible forms of exclusion. These include young people with reduced mobility, hearing impairments, visual impairments, neurodiverse youth and LGBTQ+ youth. For each group, the booklet outlines common needs, barriers that may appear in volunteering projects and practical recommendations for mentors and organisations to create inclusive environments. The booklet also introduces seven key principles for reinforced mentorship, emphasising approaches such as prioritising the volunteer, avoiding assumptions, co-creating solutions with participants, focusing on abilities rather than limitations and recognising that inclusion requires ongoing dialogue and shared responsibility. The final section offers practical guidance on implementing reinforced mentorship before, during and after volunteering projects. It includes suggestions on understanding volunteers’ needs, planning personalised support, preparing mentors, ensuring accessible environments, monitoring well-being during the activity and supporting reflection and transition after the project. Overall, the resource functions as a practical guideline for organisations that want to strengthen inclusion and provide meaningful participation opportunities for volunteers with fewer opportunities in European Solidarity Corps projects.