Book excerpt: These new Guidelines for Safe Recreational Water Environments describe the present state of knowledge regarding the impact of recreational use of coastal and freshwater environments upon the health of users - specifically drowning and injury, exposure to cold, heat and sunlight, water quality (especially exposure to water contaminated by sewage, but also exposure to free-living pathogenic microorganisms in recreational water), contamination of beach sand, exposure to algae and their products, exposure to chemical and physical agents, and dangerous aquatic organisms. In addition, control and mo.