In order to improve the survival capability of passenger and ro-ro ships in event of fire or flooding, in the last few years a set of international Regulations has been issued. In particular, the Regulation SOLAS “Safe Return to Port” is addressed towards design criteria able to guarantee adequate functionality of the ship when a casualty occurs. The Regulation requires the evacuation of the ship when a given threshold of damage (i.e., fire and flood) is exceeded. The evacuation analysis has become of primary importance even in the early-stage design. Indeed, the new amendments to SOLAS Regulation II-2/13.3.2.7 makes the evacuation analysis mandatory for both new and existing passenger and ro-ro ships since the early steps of the project. In this paper, the current IMO Guidelines have been analysed, and a case study for the evacuation of a 3600-person cruise ship has been carried out by means of both a simplified and an advanced method. To perform advanced calculations, two different software, based on virtual reality, have been used and the results have been compared with simplified method ones.