Flying is the safest way to travel and safety has always been number one priority for the aviation industry. However, since a large number of people pass through airports and travel on large planes every day, it is also an attractive target for terrorism and other forms of crime. Over the years, several methods and techniques have been developed in an attempt to safeguard passengers, staff, aircraft and airport facilities from unlawful interference threatening their security. This course gives an overview of how threats have shaped the industry and what measures are currently in place to prevent dangerous situations through reduction of chances that illegal items can enter into an aircraft, airport, or country. Flying as we know it today evolved significantly since aviations early days and in this course, we discuss the major triggers behind it. If you ever wondered why you need to take your shoes off, or why there is a ban on liquid items larger than 100ml while going through an airport security checkpoint, let us take you on a journey through historical events that gave precedence to some of the most important changes to passenger processing. After this course, you will get a better understanding of what threatens the aviation and how the industry responds to some of the well-known but also the new emerging threats.