Map showing the wards of the Orpington Parliament Constituency (red) within the London Borough of Bromley (yellow). Cray Valley West (orange) was included in the constituency at the last elections in 2005 but will be excluded from the next in 2009
Orpington was created in a mini boundary review enacted at the 1945 general election. The seats of Dartford and Chislehurst had both seen their electorate grow enormously since the last review and as an interim measure were divided into four, creating the additional seats of Bexley and Orpington. The seat has changed a little in subsequent boundary reviews since 1945, most recently at the 1997 general election, when the Ravensbourne seat was divided between the three Bromley constituencies, moving Biggin Hill into the existing Orpington seat.