The term ‘environment’ is frequently used as if it is a coherent collection of issues and considerations that are widely understood. It is also widely accepted that some transport modes and developments of them are good for the environment while others are bad. To help us grasp this simple idea the UK government have established an Environment Agency . The agency say, “it’s our job to look after your environment and make it a better place – for you, and for future generations.” How lovely! Anyway, top of the pops for environmentally “good” transport are cycling and walking. Correspondingly, any development that makes cycling or walking easier is good. Then, according to conventional wisdom, come modes used for mass transit, or Public Transport, i.e.; bus, train and tram or taxi. Conversely, some modes and transport practices are considered to be bad for the environment. Common knowledge in most ‘Western’ nations has it that all private motor vehicles are bad for the environment. Correspondingly, anything that makes use of such modes harder, be it more tax or physical obstruction, is at least no bad thing for the environment and quite probably a jolly good idea that only the brave or politically fearless might have the temerity to question. …But, as is true of just about every transport related issue the realities of whether things have a net benefit on environmental grounds are more complex and often different to the theory.