An explanation in terms of the growing threat of desiccation is given for including in a symposium on deserts some of those regions in Southern and Eastern Africa that in reality are sub-desert, arid, sub-arid and mild-sub-arid. For the regions selected brief notes are provided regarding natural setting, actual and potential productivity and threat of desiccation. A concise account covers some of the principal ecological phenomena exhibited. Productivity present and potential is discussed in relation to the exisiting and the future threat of desiccation. In conclusion it is recommended that, despite frequent and recent representation to the various governments concerned of the seriousness of the advance of desiccation, continued stressing to the authorities that action - not promise of or verbal tribute to action - must be the responsibility of thosae conversant with the dangers facing those portions of the continent under review.