Many European governments increasingly seek to return migrant children to their countries of origin or transit, but this is often not undertaken in full accordance with international obligations on children’s rights, nor with respect for children’s best interests. This report highlights the human rights obligations of the four governments under examination (those of Germany, the Netherlands, Sweden, and the United Kingdom), and the commitments that they have made respecting the return and reintegration of refugee and migrant children on their territory – particularly, to uphold these children’s best interests, regardless of their nationality or migration status. The research conducted at country level in 2019 in Germany, the Netherlands, Sweden, and the UK also focused on good practices employed by these governments in relation to returns and reintegration decisions and processes, as well as on current challenges.