Worcestershire sauce (ⁱ/ˈwʊstərʃər/ WUUS-tər-shər), or sometimes known as Worcester sauce ( /ˈwʊstər/ WUUS-tər) is a fermented liquid condiment; primarily used to flavour meat or fish dishes.

First made at 60 Broad Street, Worcester, England, by two dispensing chemists, John Wheeley Lea and William Henry Perrins, the Lea & Perrins brand was commercialised in 1837 and has been produced in the current Midlands Road factory in Worcester since 16 October 1897. It was purchased by H.J. Heinz Company in 2005 who continue to manufacture and market "The Original Lea & Perrins Worcestershire Sauce", under the name Lea & Perrins, as well as Worcestershire sauce under their own name and labelling. Other companies manufacture similar products, often also called Worcester sauce, and marketed under different brands. Additionally, in recent years recipes have begun appearing for homemade variations of the British version.

Worcestershire sauce is often an ingredient in Welsh rarebit,Caesar salad, Oysters Kirkpatrick, and sometimes added to chili con carne. Worcestershire sauce is also used to flavour cocktails such as a Bloody Mary or Caesar. Known as salsa inglesa (English sauce) in Spanish, it is also an ingredient in Michelada, the Mexican beer cocktail.

Worcestershire (ⁱ/ˈwʊstərʃər/ WUUS-tər-shər or /ˈwʊstərʃɪər/ WUUS-tər-sheer ; abbreviated Worcs) is a non-metropolitan county in the West Midlands of England. In 1974, it merged with the neighbouring county of Herefordshire to form Hereford and Worcester. This was divided in 1998, re-establishing Worcestershire as a county. The Malvern Hills forms the east–west border between the two counties, with the exception of West Malvern in Worcestershire.

The county borders Herefordshire, Shropshire, Staffordshire, West Midlands, Warwickshire and Gloucestershire. To the west, the county is bordered by the Malvern Hills and the spa town of Malvern. The southern part of the county is bordered by Gloucestershire and the northern edge of the Cotswolds; to the east is Warwickshire. There are two major rivers flowing through the county, the Severn and the Avon.

The cathedral city of Worcester is the largest settlement and administrative seat of the county, which includes the principal settlements of Bromsgrove, Stourport-on-Severn, Droitwich, Evesham, Kidderminster, Malvern, and the largest town, Redditch, and a number of smaller towns such as Pershore, Tenbury Wells and Upton upon Severn. The north of the county includes part of the industrial West Midlands conurbation while the south of the county is largely rural. The average salary is £20,300.