This chapter will discuss aspects of three popular water-based experiences: scuba diving, snorkeling, and free diving. An historical overview introduces the work, followed by a discussion of what each experience involves. The change in characteristics of the international market profile as a result of increasing demand is discussed, together with a number of relevant management issues. Consideration of issues related to these sports as recreational tourism activities leads into a review of a range of impacts that can result. The work concludes with case analysis of a popular Australian diving site, Julian Rocks, located within the Cape Byron Marine Park.