A guide to the collection, analysis and use of information about the cultural context of diarrhea - household and behavioural factors are identified in a cultural context. the aim is to facilitate the development, implementation and monitoring of programmes for the control and prevention of diarrhea. Part III is a field guide to the use of Rapid Assesment Procedures, many of which are closely related to PRA tools such as mapping, the use of key informants and checklists for informal interviews. Emphasis is placed on understanding the beleif system - how the body works, the causes and consequences of illness - and how the household and caregivers respond to diarrhea. The final section considers practical options for applying the information and testing (often through more formal methods) the generalisability of information.