This master thesis deals with the social-economic development of the Elaphiti island in the second half of the 20th century. The Elaphiti islands consist of eight islands, five small islands and several reefs and rocks; only Koločep, Lopud and Šipan are inhabited with four settlements. These islands belong to a group of small Croatian islands situated in the southest part of the Adriatic Sea. The historical background of these islands, territorial and functional growth of the settlements were presented in this master thesis. Also, the demographic facts were analyzed and presented, showing the modern demographic processes and their impact on the social growth of the Elaphiti islands. The master thesis deals also with the economic development of the islands. Activities in the primary sector dominated till the 20th century. Then came the development of infrastructure and the traffic connection as the major factor for the growth of the economic development. The master thesis deals with the tourist industry from the previous century till now as the main source of income for the local people. Many graphs and tables showed the number of tourists who came to the islands, overnight stays and the change of tourist capacities in order to point out the significance of tourist industry. The change of these islands was based on these social and economic factors, they were compared to other small Croatian islands and the island´s connection to the city of Dubrovnik was emphasized.