A heerlijkheid (a Dutch word; pl. heerlijkheden; alternative spelling heerlykheid) was the basic administrative and judicial unit in rural areas in Dutch-speaking lands before 1800. It originated in the feudal subdivision of government authority in the Middle Ages. The closest English equivalents of the word are "seigniory" (or "seigneury") and "manor". The heerlijkheid system was the version of seigneurialism or manorialism that prevailed in the Low Countries and was the precursor to the modern municipality system in the Netherlands and in the Flemish region of Belgium.

Speaking generally, a heerlijkheid was essentially made up of a village and the land extending around it for a kilometre or so. Taking 18th century Wassenaar as an example of a large hoge heerlijkheid, it was 3,612 morgens in size and had 297 houses. Nearby Voorschoten was 1,538 morgens in size and had 201 houses. Nootdorp was an ambachtsheerlijkheid of 196 morgens and 58 houses. There were 517 heerlijkheden in the province of Holland in the 18th century. All fell into the last three categories in the list below (except for a few for which this information is unknown).