The British Railways Class 24 diesel locomotives, also known as the Sulzer Type 2, were built from 1958 to 1961. One hundred and fifty-one were built at Derby, Crewe and Darlington, the first twenty of them as part of the British Railways 1955 Modernisation Plan. This class was used as the basis for the development of the Class 25 locomotives.

The Derby Works comprised a number of British manufacturing facilities designing and building locomotives and rolling stock in Derby, England. The first of these was a group of three maintenance sheds opened around 1840 behind Derby station. This developed into a manufacturing facility called the Midland Railway Locomotive Works, known locally as "the loco" and in 1873 manufacturing was split into locomotive and rolling stock manufacture, with rolling stock work transferred to a new facility, Derby Carriage & Wagon Works.