Harlow is a new town and local government district in Essex, England. It is located in the west of the county and on the border with Hertfordshire, on the Stort Valley. The town is near the M11 motorway and forms part of the London commuter belt. The district has a current population of 78,768 (2005 estimate)

The new town was built after World War II to ease overcrowding in London at the same time as the similar orbital developments of Basildon, Stevenage, and Hemel Hempstead.  The master plan for the new town was drawn up in 1947 by Sir Frederick Gibberd.  The development incorporated the market town of Harlow, now a neighbourhood known as Old Harlow, and the villages of Great Parndon, Latton, Tye Green, Potter Street, Churchgate Street, Little Parndon, and Netteswell. The town is divided into neighbourhoods, each self supporting with their own shopping precincts and community facilities. Harlow has one of the most extensive cycle track networks in the country, connecting all areas of the town to the town centre and industrial areas. The cycle network is composed mostly of the original pre-new town roads.

The town centre is notable being the location of Britain's first pedestrian precinct,and first residential tower block, The Lawn, constructed in 1951; it is now a Grade II listed building. From 1894 to 1955, the Harlow parish formed part of the Epping Rural District of Essex. From 1955 to 1974, Harlow was an urban district.

The town centre, and many of its neighbourhood shopping facilities have undergone major redevelopment, along with many of the town's original buildings. Most of the town's buildings, built at a time when concrete was widely used in construction, now suffer from conditions relating to this, both practical and aesthetic. Subsequently, many of the original town buildings, including most of its health centres, the Staple Tye shopping centre, and many industrial units have been rebuilt. The most notable of these has been the demolition of Gibberd's original town hall, a landmark in the town, and its replacement of a new civic centre and shopping area.