Any colour, as long as it’s green

The evolution of bus design has delivered radical new shapes onto city streets over the past few decades. Materials, in particular, have changed significantly, with much more use of plastics and composites, and brighter colours. The holy grail seems to be achieving something that can stand alongside the private car for style, comfort and convenience. It is a difficult challenge given that the one thing that public transport cannot provide is private space.

The international union of public...