The authors expound the reasons why population uses the daily ferry and shipping line services between Zadar and its islands, based on the poll which included 209 passengers. The obtained results indicate that the islands' population uses these services mostly for shopping purposes, medical care and less for the work or school. The highest frequency of the ferry and shipping lines is early in the morning (5-6 a.m.) for departure, and early in the afternoon (1-3 p.m.) for return. However, the available traffic connections are not strong enough to integrate the urban core on the coast with the islands, particularly with remote islands of the Zadar islands group, into unique economic entity. Insufficient number of well equipped shops, badly organized medical care, non existence of important institutions on the islands influenced a stronger depopulation. That is why the aim of the research is to show that modernisation of the ferry boat lines would positively influence on economic and demographic development of the islands.