In-flight aggression is the term used to describe aggressive behaviour during flights. The dangers such behaviour pose are evident when the lives of passengers and cabin crew are threatened. In the worst case scenario, passenger/s will barged into the cockpit and interfere with flight controls, causing the aircraft to crash while losing all lives onboard. This study investigates the magnitude of in-flight aggression and some of the triggers that lead passengers to it. It also examines the effectiveness of some measures and the environment which in-flight aggression manifest. The results showed that cabin crew were exposed to the serious dangers of in-flight aggression 6 times more than an average passenger. After September 11th, passengers became more aware of the dangers of in-flight aggression and were more willing to assist cabin crew should the need arise. Alcohol was found to be the top trigger of in-flight aggression and cabin crew intervention of such behaviour is most effective compared to other measures such as flight crew, other passengers, legislation, etc. Some aspects of airline policies and procedures related to the management of in-flight aggression require attention. Pre-flight and in-flight procedures and policies were only moderately effective and experienced cabin crew found them disappointing. Airlines encourages their crew to report incidents and have high safety standards which they expect cabin crew to adhere to strictly, failing which cabin crew are likely to face disciplinary actions. However the cabin crew were seldom informed about outcome of incidents and lessons drawn from incidents seldom led to policy or procedural improvements. Cabin crew believed that both physical and psychological passenger management techniques should be incorporated in training and many would like to be trained in self-defence although many airlines do not provide such training. There is some evidence that profiles of passenger and cabin crew can be used to predict a potential perpetrator and the effectiveness of a cabin crew managing an incident. Based on the finding, several recommendations were made to better manage in-flight aggression.