The monarchy of Saint Vincent and the Grenadines is the constitutional system of government in which a hereditary monarch (shared with several other Commonwealth countries) is the sovereign of Saint Vincent and the Grenadines, forming the core of the country's Westminster-style parliamentary democracy. The Crown is thus is the foundation of the executive, legislative, and judicial branches of the Vincentian government.
While Royal Assent and the royal sign-manual are required to enact laws, letters patent, and orders in council, the authority for these acts stems from the Vincentian populace, and, within the conventional stipulations of constitutional monarchy, the sovereign's direct participation in any of these areas of governance is limited, with most related powers entrusted for exercise by the elected and appointed parliamentarians, the ministers of the Crown generally drawn from amongst them, and the judges and Justices of the Peace.
King Charles III acceded to the throne on 8 September 2022 upon the death of his mother, Queen Elizabeth II, becoming the Head of State of a number of realms of the Crown, including Saint Vincent.
In Saint Vincent and the Grenadines King Charles III is styled: "His Majesty Charles the Third, by the Grace of God, King of Saint Vincent and the Grenadines and His other Realms and Territories, Head of the Commonwealth" (thus omitting the "Defender of the Faith" title used in the United Kingdom and some other realms).
The monarch, besides reigning in Saint Vincent and the Grenadines, separately serves as monarch for a number of other Commonwealth countries known as Commonwealth realms. This developed from the former colonial relationship of these countries to Great Britain, but they are now independent of each other and are legally distinct.