Smiths Group plc (LSE: SMIN) is a global diversified company headquartered in London, United Kingdom. It has operations in over 50 countries and employs around 23,550 staff.

Smiths Group has five divisions. Smiths Detection is the world's largest manufacturer of sensors for the detection of explosives, weapons, chemical agents, biohazards, narcotics and contraband. John Crane is a major manufacturer of seals and associated products for the process industries. Smiths Medical is a major supplier of medical devices and equipment. Smiths Interconnect is a major manufacturer of electronic and radio frequency products. Flex-Tek is a major supplier of components to heat and move fluids and gases.

Smiths Group is listed on the London Stock Exchange and is a constituent of the FTSE 100 Index.

The company was founded by Samuel Smith in London in 1851 as a clock and watch business. At the start of the 20th century, the age of the early automobiles, the company produced the first British odometer ("mileometer") and speedometer. In the 1930s Smiths agreed a trading deal with Lucas whereby the two would not compete in certain areas and Lucas took on part of Smiths non-instrumentation assets. Smiths became the dominant supplier of instruments to British motorcar and motorcycle firms. From 1915 Smiths had a factory at Cricklewood, north London and later moved their headquarters there.