The general development towards simulation-based design has been supported and in some cases even driven by modern classification society work. Advanced finite-element analysis has long been part of the services of classification societies. However, more recently the scope and depth of simulations at Germanischer Lloyd have developed rapidly and a survey of the techniques used as well as typical applications is given. The article focuses on basics of the techniques, pointing out progress achieved and current research activities, giving references that describe in more detail the individual applications and simulation techniques.