The link between tourism development and accessibility is very important for island destinations, whose connectivity to the mainland depends entirely on sea and air passenger transport services. In this chapter, we analyze patterns of transportation for tourists and residents via ferry and airplane for a number of Greek Aegean islands and groups of islands. These represent distinct cases in terms of accessibility and tourism recognition: one very popular international destination (Santorini); one case of an international destination with a number of satellite islands (Rodos with Chalki, Symi and Tilos); and two less important cases in terms of international tourism (Lesvos, and Naxos with its satellites: Donoussa, Schinoussa, Herakleia and Koufonissi). The findings suggest that a number of different archipelagic clusters emerge within the Aegean Sea, determined largely by existing transport routes and tourism development trajectories.