In this report I study the speech varieties of Swahili in the coastal area of Tanzania and on the nearby islands of the Indian Ocean. The study material consists of the tape-recorded speech of various people. The material was collected as part of the so-called DAHE project in 1989 - 1991. The aim of the project was to initiate the Computer Archives of Swahili Language and Folklore. The counterparts of the project were the University of Helsinki and the University of Dar-es-Salaam. The project produced two types of material, (a) recorded speech on various topics, and (b) wordlists from various speech areas, 620 words in each list. In this report, the first type of material is discussed.