The constituency covers the towns of Sleaford and North Hykeham and a large area of rural Lincolnshire south west of Lindsey. The constituency's boundaries roughly correspond to those of North Kesteven local government district. In their formative proposals for 1997, the Boundary Commission for England proposed calling the new constituency Mid Lincolnshire, however the name was changed to its current form during the local inquiry process. The inclusion of North Hykeham in the constituency title was criticised by the author and psephologist Robert Waller in 1995, on the grounds that North Hykeham was effectively an overspill area of the City of Lincoln; however, not on the grounds of its actual inclusion, as its local government authority has long been seen as linked with the villages to the south in this seat, and wholly separate from the city.