A midibus is a classification of single-decker minibuses which are generally larger than a traditional minibus but smaller than a full-size single decker and can be anywhere between 8 metres and 11 metres long. While used in many parts of the world, the midibus is perhaps most common in the United Kingdom, where operators have found them more economical, and to have a sufficient number of seats compared to full size single-decker buses.

The Alexander Dennis Enviro200 MMC, also marketed as the Alexander Dennis Enviro200, is a single-decker city bus produced by Alexander Dennis since 2014 as the successor to the Enviro200 midibus and Enviro300 full-size bus. The first Enviro200 MMCs entered service with National Express West Midlands in 2015. Notably, Enviro200 MMCs have been modified by Fusion Processing to be used as the basis for the first driverless bus trials in the United Kingdom.