Greater understanding of social inclusion is vital to decision making about mainstreaming nature-based solutions. Social inclusion in this context means understanding how vulnerable, marginalised and under-represented voices are included (rather than excluded) in processes and practices to mainstream nature-based solutions. Although nature-based solutions and social inclusion are usually addressed separately, there are a myriad of connections between them. Drawing on extensive research on the opportunities and pathways for mainstreaming nature-based solutions in six countries in Europe and at EU level, this report identifies four pathways to mainstream nature-based solutions for social inclusion.