Maritime piracy is now recognised as a critical security problem that attracts news coverage worldwide. The International Maritime Organisation recommends a series of ship protection measures to be used by vessels travelling at sea to prevent and disrupt pirate attacks. However, limited research exists on the effectiveness of these situational measures, and the few formal studies that do exist are not able to capture the realities of how these measures are employed by ships. This study examines the impact of combinations of ship protection situational measures on maritime pirate attacks. Drawing on data collected and released in International Maritime Bureau Annual Reports from 2010-2011, 452 cases of pirate attacks were coded and analysed. Results suggest the use of Watch Keeping and Enhanced Vigilance and a minimum of two protective measures dramatically increase the chances of thwarting pirate attacks. This result strongly supports the adoption of ship protection measures recommended by the International Maritime Organisation to prevent piracy.