Cambridge Systems Technology (CST) was a company formed in the early 1980s by ex-Torch Computers engineers David Oliver and Martin Baines, to produce peripherals for the BBC Micro, and later, with Graham Priestley, Sinclair QL microcomputers. Products included IEEE 488, floppy disk and SCSI interfaces. Following the demise of the Sinclair QL in 1986, CST began producing the Thor series of QL-compatible personal computers. These had limited commercial success, and CST had ceased trading by the end of the decade.