Chesham (, , or ) is a market town and civil parish in Buckinghamshire, England. It is 11 miles (18 km) south-east of the county town of Aylesbury and 25.8 miles (41.5 km) north-west of Charing Cross, central London, and is part of the London commuter belt. It is in the Chess Valley and surrounded by farmland. The earliest records of Chesham as a settlement are from the second half of the 10th century although there is archaeological evidence of people in this area from around 8000 BC. Henry III granted the town a royal charter for a weekly market in 1257.
Chesham is known for its four Bs — boots, beer, brushes and Baptists. In the face of fierce competition from both home and abroad the three traditional industries rapidly declined. The ready availability of skilled labour encouraged new industries to the town both before and after the Second World War. Today, employment in the town is provided mainly by small businesses engaged in light industry, technology and professional services.
From the early part of the 20th century, there has been a considerable expansion with new housing developments and civic infrastructure. Chesham has become a commuter town with improved connection to London via the London Underground and road networks. The town centre has been progressively redeveloped since the 1960s and has been pedestrianised since the 1990s. The population at the 2011 Census was 21,483.