Over the years, a succession of alternatives to steam turbine propulsion for large LNG carriers has been rolled-out by the marine engineering industry. Nonetheless, the steam turbine has continued to reign supreme for four decades, since the start of large-scale LNG transportation by sea, in what now constitutes its last bastion in the commercial vessel sector. This achievement is a reflection of the performance and proven attributes of such plant, rather than an indictment of alternative solutions. For sure, one of the steam turbine's most valued qualities is its reliability, with all which that implies for service dependability, ship productivity and safety. Another is the facility, which it offers for burning liquefied cargo boil-off as readily as fuel oil.