Mental capacity refers to a person’s ability to understand, retain, weigh up, and communicate information in order to make a specific decision.
It is decision‑ and time‑specific, meaning a person may have capacity for some decisions but not others, and this can change.
This matters because UK law, the Mental Capacity Act, is designed to empower people to make their own decisions wherever possible and to ensure that any support or best‑interest decisions are made safely, respectfully, and with the least restriction on a person’s autonomy.



