This document summarizes research on the commonalities between airline and sea hijacking. It finds that as aviation security increased, reducing airline hijackings, sea hijackings have risen using similar tactics. Statistics show peaks in both forms of hijacking correlate with political events. Case studies of the 1985 TWA Flight 847 hijacking and 1985 Achille Lauro hijacking are described to illustrate the tactics. The document discusses rational choice and deterrence theories in relation to preventing hijackings and concludes more must be done to improve transportation security universally against this threat.