Drawing on the work of Coram Children’s Legal Centre (CCLC) through its Migrant Children’s Project advice line, outreach services and legal casework, this report examines the ways in which lack of immigration status is an obstacle to children and young people accessing their basic rights and entitlements and the difficulties this group face in regularising their status and obtaining essential legal advice. Undocumented migrant children are amongst the most vulnerable in the UK and the most at risk of exceptional poverty and destitution. While the importance of developing a more effective immigration system cannot be denied, such a system must go hand in hand with the UK’s human rights obligations to children. In CCLC’s experience, many undocumented migrants currently living in the UK have very strong legal claims to remain, but face obstacles to regularising their status. These obstacles include: • Lack of awareness of their legal rights • Inability to understand the extremely complex Immigration Rules • Misinformation about legal rights and routes to regularisation • Lack of access to legal advice and representation, including the absence of legal aid for non-protection immigration cases • Reluctance on the part of solicitors and legal representatives to take on certain cases • Unaffordable application fees for Home Office applications • Lack of co-operation by partners, including in situations of abuse and domestic violence • Fear. This leaves a population of children in limbo without a regular immigration status or access to services, but unable to leave the UK.