Although largely undamaged in the First and Second World Wars, Sleaford has close links with the Royal Air Force due to its proximity to several RAF bases, including RAF Cranwell and RAF Waddington.
Lincolnshire's topography—flat and open countryside—and its location on the east of the country made it ideal for the development of Britain's airfields, constructed in the First World War.
Work began on Cranwell in late 1915; it was designated an RAF base in 1918 and the RAF College opened in 1920 as the world's first air academy.
The Cranwell branch railway linking Sleaford station to the RAF base opened in 1917 and closed in 1956.
During the Second World War, Lincolnshire was "the most significant location for bomber command" and Rauceby Hospital, south-west of Sleaford, was requisitioned by the RAF as a specialist burns unit which plastic surgeon Archibald McIndoe regularly visited.

In the inter-war period, Sleaford's population remained static, but the Great Depression in the 1930s caused unemployment to rise.
Council-housing developments along Drove Lane proved insufficient to house low-income families after the Westgate slums were cleared in the 1930s so Jubilee Grove opened in that decade to meet the demand.
In the post-war period, there were new housing developments at St Giles Avenue, the Hoplands, Russell Crescent, Jubilee Grove and Grantham Road.
Parts of the town were redeveloped: in 1958, the Bristol Arms Arcade opened, the Corn Exchange was demolished in the 1960s and the Waterside Shopping Precinct opened in 1973, as did Flaxwell House, designed to house a department store, though later becoming the national headquarters for Interflora.

By 1979, the major landowner, Victor Hervey, 6th Marquess of Bristol, heavily in debt, had sold most of his estates in Sleaford and Quarrington and the estate's office closed in 1989.
Much of the land was sold to property developers and in the following decades saw the construction of residential buildings and a considerable population increase.
According to a council report, "the quality of life, low crime rates, relatively low house prices and good-quality education" attracted people to the town.
From 1981 to 2011, Sleaford's population rose from 8,000 to 18,000; the growth rate from 1991 to 2001 was the fastest of any town in the county.
Its infrastructure struggled to cope, especially with increased traffic congestion; two bypasses around the town and a one-way system were introduced, a process which Simon Pawley argues accelerated the decline of the High Street.
In the early 2000s, the Single Regeneration Budget of £15 million granted to Sleaford improved the town centre and funded development of the Hub (since 2011, the National Centre for Craft & Design) in the old Navigation wharves area.
Although largely undamaged in the First and Second World Wars, Sleaford has close links with the Royal Air Force due to its proximity to several RAF bases, including RAF Cranwell and RAF Waddington. Lincolnshire's topography—flat and open countryside—and its location on the east of the country made it ideal for the development of Britain's airfields, constructed in the First World War. Work began on Cranwell in late 1915; it was designated an RAF base in 1918 and the RAF College opened in 1920 as the world's first air academy. The Cranwell branch railway linking Sleaford station to the RAF base opened in 1917 and closed in 1956. During the Second World War, Lincolnshire was "the most significant location for bomber command" and Rauceby Hospital, south-west of Sleaford, was requisitioned by the RAF as a specialist burns unit which plastic surgeon Archibald McIndoe regularly visited.
In the inter-war period, Sleaford's population remained static, but the Great Depression in the 1930s caused unemployment to rise. Council-housing developments along Drove Lane proved insufficient to house low-income families after the Westgate slums were cleared in the 1930s so Jubilee Grove opened in that decade to meet the demand. In the post-war period, there were new housing developments at St Giles Avenue, the Hoplands, Russell Crescent, Jubilee Grove and Grantham Road. Parts of the town were redeveloped: in 1958, the Bristol Arms Arcade opened, the Corn Exchange was demolished in the 1960s and the Waterside Shopping Precinct opened in 1973, as did Flaxwell House, designed to house a department store, though later becoming the national headquarters for Interflora.
By 1979, the major landowner, Victor Hervey, 6th Marquess of Bristol, heavily in debt, had sold most of his estates in Sleaford and Quarrington and the estate's office closed in 1989. Much of the land was sold to property developers and in the following decades saw the construction of residential buildings and a considerable population increase. According to a council report, "the quality of life, low crime rates, relatively low house prices and good-quality education" attracted people to the town. From 1981 to 2011, Sleaford's population rose from 8,000 to 18,000; the growth rate from 1991 to 2001 was the fastest of any town in the county. Its infrastructure struggled to cope, especially with increased traffic congestion; two bypasses around the town and a one-way system were introduced, a process which Simon Pawley argues accelerated the decline of the High Street. In the early 2000s, the Single Regeneration Budget of £15 million granted to Sleaford improved the town centre and funded development of the Hub (since 2011, the National Centre for Craft & Design) in the old Navigation wharves area.
Sleaford