Every year multiple outbreaks occur in treated recreational water due to improper sanitation and hygiene practices. This talk will review pathogens and swimmer behaviors that can lead to recreational water illnesses (RWIs). Treatments used to prevent RWIs will be discussed, along with tools that health inspectors can use to ensure that the treatments are working effectively and that facility operations are optimized for disease prevention. The current recommendations from the 2018 Model Aquatic Health Code will be incorporated throughout the talk.