In rural settlements of the Kenya Coast C. p. quinquefasciatus develops in three major types of breeding-places. These are pit latrines, cesspools and small cement cisterns which man builds to improve his sanitary facilities. All three types are present in Moslem villages. At present only latrines have been recorded in non-Moslem villages. Building of such facilities is an established practice in Moslem villages while it is recent in non-Moslem ones. The proportion of houses with potential breeding-places is increasing with the standard of living of the inhabitants and with the size of the settlements. Since the building of sanitary facilities will probably increase in the future the mosquito breeding situation will tend to worsen accordingly. Thus there is an urgent need to curb such breeding by developing low cost technology which can easily be implemented.