This Manual provides practical guidance on how to produce durable concrete in rural environments of developing countries using local materials. It is aimed primarily at the practising Engineer who may be faced with using local materials of either low quality or for which there are no data available and it is often faced with using British and American Standards which are developed for different materials and are not entirely relevent to the local materials of developing countries. Guidance is provided for producing low to medium strength, durable concrete for mass and reinforced concrete structures with the most effective use of local materials taking into account environmental conditions, the intended life span of the structure and its in-service requirements.