The third edition of a practical guide for teaching health workers how to assess diarrhea and dehydration, treat cases effectively, and convince community members to adopt preventive practices. Didactic in its approach, the manual uses simple language supported by abundant charts, tables, checklists, and illustrations to help readers absorb information and acquire the full range of essential skills. The book opens with a clear explanation of what diarrhea is, why dehydration is so dangerous, and how a child with diarrhea should and should not be treated. The second section, devoted to home treatment, elaborates three basic rules for helping mothers and other family members treat diarrhea in the home. Of particular practical value are sections designed to teach health workers how to assess and treat patients. Instructions for assessment are presented through a list of questions to ask, conditions to investigate, and signs to observe, followed by a detailed assessment chart and illustrative examples of how the chart works in practice. The section on treatment provides step-by-step instructions for the preparation of a solution from oral rehydration salts, and sets out three detailed plans, correlated with columns in the assessment chart, for the treatment of diarrhea, dehydration, and severe dehydration. The guide also outlines the treatment of dysentery and cholera, and discusses what health workers can do to help prevent diarrhea by making community members aware of preventive practices and encouraging their adoption. A checklist of essential points to remember concludes the book.