Pioneering Spirit is a catamaran crane vessel owned by the Switzerland-based Allseas Group designed for the single-lift installation and removal of large oil and gas platforms and the installation of record-weight pipelines. The 382-metre-long (1,253 ft), 124-metre-wide (407 ft) vessel is the world's largest vessel by gross tonnage, the heaviest vehicle ever made and since September 2021 also the largest floating sheerleg in the world. It was built in South Korea by Daewoo Shipbuilding & Marine Engineering in 2013 at a cost of €2.6 billion. It commenced offshore operations in August 2016.

A crane vessel, crane ship, crane barge, or floating crane is a ship with a crane specialized in lifting heavy loads, typically exceeding 1,500 t for modern ships. The largest crane vessels are used for offshore construction.