Reducing global emissions of greenhouse gases while promoting social and economicdevelopment is one of the toughest challenges ever faced in the history of human kind.This challenge is affecting all sectors of human activities: process plants, land-basedtransportation, residential buildings. In this framework, the maritime industry faces no smaller challenge. Sea trade and the cruise industry keep growing despite economic crises,while CO2 emissions from shipping need to fall, as for any other sectors, need to fall.This report, main deliverable of the ODes aCCES project (Optimal Design and Control of Cruise ship Energy Systems) is meant to provide the interested reader with relevant information to be used in the process of optimizing the design of ship energy systems,and particularly those of cruise ships. The report presents a broad review of different optimization strategies and methods; of methods specifically developed for the optimization of energy systems; and of the application of such methods to the optimization of ship energy systems