This presentation will explore the transformative role of simulation in the development of autonomous maritime systems. Looking across the whole engineering cycle, the speaker will delve into how advanced simulation techniques enhance design accuracy, reduce costs and accelerate development timelines. By examining key methods, the presentation will illustrate how simulation identifies potential design flaws, optimizes performance and ensures regulatory compliance. Furthermore, it will examine the synergy between simulation and real-world testing, highlighting their combined effectiveness in advancing the field of autonomous maritime technology.