This paper presents the current results of a continuing survey of the distribution, status and biological importance of Tanzanian coastal forests. The Frontier-Tanzania Coastal Forest Research Programme has shown that at least 34 locations, and possibly another eight, support important coastal forests. There are probably 350–500 sq km of forest remaining, with most sites smaller than 20 sq km. Most sites, and 75–85 per cent of the total area, are located in Forest Reserves. Coastal forest supports many endemic taxa and many individual forests support species and subspecies known from nowhere else. All these forests are severely threatened and effective conservation action is a priority. The Frontier-Tanzania project findings are contributing to conservation programmes co-ordinated by the Wildlife Conservation Society of Tanzania and the World Wide Fund for Nature (Tanzania).