Family office
Also: single-family office, multi-family office
An organisation that manages the wealth and affairs of one or more wealthy families.
A family office oversees the full balance sheet of a wealthy family, from investments to governance and succession. A single-family office serves one family; a multi-family office serves several.
A family office professionalises the management of wealth, but it is itself a business with real costs, typically a third to nearly a half of a percent of assets a year. Whether to build one, join a multi-family office, or outsource is among the more consequential decisions a wealthy family makes.