The maritime model will be used to analyse the future commercial viability of a number of new technologies and calculate their impact on the UK’s future CO2 emissions. In order to carry out these estimations, a scenario is required which will describe the context in which shipping (and UK shipping) will be operating in in the future. In this report, the scenario is broken down into forecasts for a number of external factors, a value proposed for the external factor and justification given for its selection. The following are considered: - Regulation - Fuel and carbon price - Shipping markets - Transport demand (trade and routing) - Infrastructure - BAU technology In addition to each of these areas, some of the modelling parameters are defined including fleet and region taxonomies and apportionment philosophy for accounting for international shipping’s CO2 emissions.