Carlyle Works was the central engineering works for Midland Red, once one of the largest bus operators in the United Kingdom. The company was famous for building its own buses and coaches, under the BMMO name. These buses were typically very innovative and were the first to introduce many advanced features. When the development and production of its own vehicles became prohibitive in the late 1960s the central works continued to provide heavy engineering services for the company. In 1968 Midland Red became part of the National Bus Company, and Carlyle Works provided engineering services for other National Bus Company operators. These services included major vehicle modifications and adaptations.