I don't like getting patted down and taking off my shoes at the airport Rebecca Miller. Having spent time on the broader aspects of the economics of transportation security, we now move to a series of chapters that focus on particular issues and specific modes. These are in a way extended case studies that within them have more details of the particular nuances involved in making various aspects of transportation provision and use more secure. Choices of what to include are made in part on the grounds of the importance of the topic, but also reflect the degree of material available and the studies completed on each. We begin with air transportation. At certain times, particular modes of transportation attract more security attention than their strict importance in the economy in terms of their contributions to National Income would seem to justify. At the end of the twentieth century, and into the twenty-first, air transportation has largely fulfilled this role. Although in countries such as Israel, bus bombs have been widely used, as have car bombs in Iraq, they tend to be more localized in their impacts and seldom pose a major threat to international transportation or huge numbers of people.