This chapter considers safety aspects of four common transport modes - air, sea, rail, and road. These operate in many different ways, for example all involve commercial (passenger and freight) and private travel (albeit a minute proportion of rail traffic). Managing the safe operation of each of these modes, involving numerous complex interactions, requires many specialist functions. Table 11.1 summarizes major categories within each travel mode, including commercial, commuting, leisure, and other forms. Transport is a ubiquitous feature of all our lives with most people undertaking some form of daily travel, while transport brings food and meets other survival needs. As a relatively recent evolutionary development, humans have adapted quickly to the myriad forms of transportation now available, including coping with the inherent complexity of many forms of travel. For example, driving a vehicle involves the most complicated series of tasks that most of us ever engage in, exceeding the complexity of most jobs between daily commutes. Public transport may involve protracted check-in and security processes (Williams, 2007), while interfaces between transport modes may create additional challenges.