Convincing people to adopt preventive health behaviors consistently is difficult, yet many lives could be saved if we understood better how to do so. For example, low-cost point-of-use (POU) technologies such as chlorine and filters can substantially reduce diarrheal disease (Clasen et al....

Uptake of safe water products remains low, in spite of modest cost. We experimented with a sales offer that combined a free trial and rent-to-own payments for durable filters. Purchase rates doubled under this sales offer to 31% compared to a traditional lump-sum sales contract. To lower...