Piracy is one of the most frequent maritime threats. However, despite the importance of how maritime piracy is to be reduced, it is substantially less investigated than maritime safety. Piracy off Somalia is the most investigated case of piracy, but those results are not necessarily generalizable. Piracy off West Africa has been shown to be more diverse, successful and dangerous. This study investigates and analyses piracy off West Africa with the aim to understand how different operations and security measures affect the consequences of piracy. This study has identified several different intents and shows that most attacks are relatively close to shore and correspond to areas of high ship density. Attacks with the intent of theft at night-time are generally performed close to shore, and more complicated attacks against ships under way are more common during daytime and farther from shore. Five types of measures are found to have high effectiveness if the attack is detected during approach; after boarding, only two measures have high effectiveness. Of the effective measures, it can be concluded that all but one are dependent on detecting the attack. Therefore, detecting the pirates is key but must be accompanied by a set of measures because no measure alone can protect a ship given the operational conditions off West Africa. The risks associated with piracy off West Africa are estimated to be of the same magnitude as the risks posed by Somali piracy at its peak.