The Paris Agreement, UK and Scotland Climate Change Acts provide a clear direction of travel for greenhouse gas (GHG) emissions. Scotland’s climate targets would require that the domestic transport sector be nearly completely decarbonised. Existing analysis shows that there are inefficiencies in the procurement of ferries, both in Scotland and the rest of Europe, which mean that energy efficiency and decarbonisation opportunities may be forgone in certain situations. The age of ferries has a direct impact on their efficiency and the analysis shows that, whilst Scottish ferries are younger than their counterparts elsewhere, when disaggregating by operator, there seems to be some correlation between public and private operators with regards to age of the ferries. Implementation of incremental energy efficiency technologies and measures in ferries may be hindered due to market failures, and total decarbonisation may be hindered by non-market failures