This paper explores the course of infant and childhood mortality in the Greek island of Paros from the end of the nineteenth until the mid-twentieth century. For this purpose the method of family reconstitution has been applied to two towns on the island. Official population statistics have been used to derive basic mortality estimates for the Cyclades and Greece as a whole. Reference to other studies concerning island mortality is also made. Hence, there appears the chance to compare insular with mainland mortality and realise that insular mortality presented some distinct features. It is shown that island populations presented lower mortality than the national average until the first decades of the twentieth century. However, by the 1950s Greece’s infant and childhood mortality had dropped to the same or even to lower levels than those of the islands.