A muster drill is a mandatory safety drill that takes place at the beginning of a cruise, typically before the ship sets sail. During the drill, passengers are instructed on important safety information, such as how to don a life jacket and where to assemble in the event of an emergency. The drill is conducted in a designated assembly area, usually on deck, and attendance is taken to ensure that all passengers have received the safety information. The muster drill is an important safety measure to prepare passengers for potential emergencies while on board the ship.