Boarding was of particular importance in the 17th and 18th centuries' "guerre de course", or commerce raiding, as well as to privateers and pirates. Because naval crews were paid prize money for bringing back enemy merchant shipping and cargoes intact, it was preferable to capture such ships rather than sink them, which ultimately required boarding, with or without a preliminary artillery duel. Privateers and pirates found boarding even more necessary, as both depended entirely on capturing merchant vessels for their livelihood, under the wageless system of "no purchase, no pay."