Senior plc is the holding company for a global group of firms in the manufacturing and engineering industries, headquartered in Rickmansworth, England.

[2] It acquired GAMFG Precision LLC, a manufacturer of machined components and assemblies for the off-road land vehicle and aerospace markets, for US$45.0 million in 2012.

[5] It bought UPECA Technologies, a Malaysian-based manufacturer of high-precision engineered components serving the aerospace and energy sectors, in 2014.

[6] It acquired Lymington Precision Engineering, a manufacturer of precision-machined components, fabrications, assemblies and kit sets, for a minimum of £45.8 million in 2015.

[8] In June 2021 the company rejected a $1.2 billion buyout offer from US private-equity firm Lone Star.