Alexander Dennis is best known for its internationally exported Fire Engines and Double Decker buses used in countries all around the world. It is also one of the major bus manufacturers for the United Kingdom. After its company restructuring, Alexander Dennis decided it was worth the expensive investment to alter its Enviro 400 and 500 models for export to the United States and Canada. Two markets which haven't been as receptive to Double Deckers in the past have now begun to show interest and it has paid off as many transit agencies in the United States and Canada are considering Double Deckers over Articulated Buses.

Hong Kong (a former British Territory which still drives on the right) has been one of Alexander Dennis' major export markets as Hong Kong has a high demand for double decker buses. Special versions have been built for the Hong Kong market which feature tighter turning radius and high capacity air conditioning. In North America most Alexander Dennis buses are used in Tourist sightseeing operations where the buses have an "open-top" configuration. However some agencies are exploring double deckers for transit applications as well.

Although many Tour Bus operators are protesting the use of double deckers in a transit setting, plans have moved forward in many American and Canadian cities to use them. Alexander Dennis frequently brings its factory demonstrator to Transit events to show procurement officers who may be interested. They also loan factory demonstrators to transit agencies curious about them as a trial.