In the recent years, islands, and especially tropical and subtropical islands, have become one of the most popular tourist destinations. The basic obstacle in their development for tourist purposes, that is the distance from the places of residence of potential clients, has been overcome by the introduction of large-capacity, long-haul airplanes. This happened in the late 1960s, and was followed by the construction of airports and airfields on the islands, which were more and more frequently visited by tourists from rich countries. Better accessibility, relatively lower travel costs and increasing opulence of the visitors was accompanied by the marketing of the islands as "tourists' heaven". Since the 1970s, the islands have become synonymous with the three "S'' (sea, sun, sand), soon to change to four "S'' (sex). The researchers and marketing companies from the rich countries and island regions (for practical reasons) have been constantly seeking new attributes that would help "sell" the tropical islands as a tourist product even better. Thus, in the early 21st century, there are ten "S", standing for: sand, scenery, sea, sun, surf, shopping, safety, sex, sincerity, sociability (Crocombe 2001). Table 1 is an attempt to summarise the natural potential for tourism of various types of tropical islands. The three spheres, that is, water, land and air, were translated into five "S". The characteristics of particular types of islands served as a basis for the evaluation of individual assets. Thus, sea implies the possibility of sea bathing, diving, fishing. Surf means the evaluation of opportunities for windsurfing; sand - for sunbathing on the beach; scenery - for hiking, cycling, horse riding activity aimed to explore the natural scenery. However, scenery also means possibilities for special interest tourism, e.g. mountain climbing and paragliding. Finally, sun means that the weather for a considerable portion of the year fulfils the three aforementioned characteristics of the "climatic ideal". The table implies that "near atolls", atolls and islands of continental origin located far off the coast have the best natural potential for tourism. While in the case of "near atolls'' and islands of continental origin, the tourist potential is relatively evenly spread among the three spheres (water, land and air), in the case of atols such potential lies primarily in "the warer and the sun". The tourist potential of old volcanic islands, offshore islands of continental origin and islands of the arc - ditch is mutually similar. In terms of natural potential for tourism, elevated atolls are the least attractive. Similarly, young volcanic islands are not very attractive; their main attraction lies in the interior. Research has proved that the greatest natural potential for tourism can be found in the islands of central and western Indian Ocean and in Polynesia. The Caribbean and the Mediterranean islands, Malaysia, Micronesia and Melanesia are definitely inferior to the above islands, and mutually similar. Surprisingly, islands of the eastern Atlantic Ocean have a small natural potential for tourism, mainly due to their genetic diversity (lack of coral reef).
