CLTS is an innovative methodology for mobilizing communities to conduct their own appraisal and analysis of open defecation (OD), stimulating a collective sense of disgust and shame among community members as they confront the crude facts about mass OD and its negative impacts. The basic assumption is that no human being can stay unmoved once they have learned that they are ingesting other people’s feces. Communities generally react strongly and develop action plans to become open defecation free (ODF) through their own effort based on different motivations. CLTS focuses on behavior change, triggering the community’s desire for change and encouraging innovation, mutual support and appropriate local solutions, thus leading to greater ownership and sustainability. It accomplishes all of this without external subsidies. Facilitators and natural leaders in more than 25 countries now enable this process, developed by Kamal Kar in Bangladesh in the year 2000.