Arran Poyser worked in the former remand and approved school children's residential care sectors followed by a period with the probation and after care service. He held senior management posts in London Social Services departments before being appointed to the Social Services Inspectorate at the Department of Health and Social Security where he contributed to the preparation of the Children Act 1989, the UK report on the UN Convention on the Rights of the Child and support to the guardian ad litem services across England and Wales. He was involved with the Consultation Paper Support Services in Family Proceedings: Future Organisation of Court Welfare Services before helping to establish the Children and Family Court Advisory and Support Service (Cafcass) in 2001 after which he held lead Inspection responsibilities for that Service for seven years.