The Chiltern Hundreds is an ancient administrative area in Buckinghamshire, England, composed of three hundreds and lying partially within the Chiltern Hills. Taking the Chiltern Hundreds refers to the legal fiction used to resign from the House of Commons. Since Members of Parliament are not permitted to resign, they are instead appointed to an office of profit under the Crown, which requires MPs to vacate their seats. The ancient office of Crown Steward for the Chiltern Hundreds, having been reduced to a mere sinecure by the 17th century, was first used by John Pitt in 1751 to vacate his seat in the House of Commons. Other titles were also later used for the same purpose, but only the Chiltern Hundreds and the Crown Steward and Bailiff of the Manor of Northstead are still in use.