Custody (of a child) refers, in everyday legal practice, to who is responsible for a child’s day‑to‑day care, where the child lives, and who makes key decisions about upbringing. In modern UK and Irish family law, however, “custody” is largely a non‑technical or historic term.In England and Wales and Northern Ireland, legislation now uses “parental responsibility”, “child arrangements orders” (living with/contact) or “residence” and “contact”, rather than “custody” and “access”. In Scotland, the Children (Scotland) Act 1995 and subsequent case law refer to “parental responsibilities and rights”, including responsibility to provide guidance and regulate residence, instead of custody. In Ireland, “custody” still appears in legislation and case law, but is understood alongside “guardianship” (long‑term decision‑making) and “access”.Across all four jurisdictions, disputes formerly described as “custody battles” are now framed in terms of residence, contact and parental responsibility/rights. Practitioners must be careful when drafting, advising or interpreting orders, to distinguish between historic “custody” terminology and the current statutory framework determining care, residence and decision‑making for children.