The Crown Office, a section of the Ministry of Justice, has custody of the Great Seal of the Realm, and has certain administrative functions in connection with the courts and the judicial process, as well as functions relating to the electoral process for House of Commons elections, to the keeping of the Roll of the Peerage, and to the preparation of royal documents such as warrants required to pass under the royal sign-manual, fiats, letters patent, etc.

[1] From 1885 onwards, the office of Clerk of the Crown in Chancery has always been held by the Permanent Secretary to the Lord Chancellor's Department (now the Ministry of Justice).

The Clerk of the Crown is formally appointed by the monarch under the royal sign-manual;[2] they must take an oath before assuming the office, which is now administered by the Lord Chancellor.

Since 1885, the office of Clerk of the Crown in Chancery has been combined with that of Permanent Secretary to the Lord Chancellor's Department (now the Ministry of Justice).

The Clerk of the Crown in Chancery also prepares a Return Book, listing the names of all those who are returned as members of the House of Commons in a general election, and delivers that book to the Clerk of the House of Commons on the first day of a new parliament.