For people affected by disaster, whether wars, earthquakes, or disease epidemics, conditions of life can change suddenly and in ways that require rapid adjustments. Often, adaptation includes taking greater care to prevent transmission of disease, in order to minimize the new threats to public health. Understanding what enables and influences changes in human behavior is key to developing and evaluating strong hygiene programs, so Eawag placed the issue—and the science—of behavior change front and center in its study.