CATS is UNICEF’s core strategy to eliminate open defecation, in line with Sustainable Development Goal (SDG) 6.2: to ‘achieve access to adequate and equitable sanitation and hygiene for all and end open defecation, paying special attention to the needs of women and girls and those in vulnerable situations’.4 CATS has scaled up rapidly since its 2008 inception, with implementation in over 60 countries: approximately 48 million people now live in open defecation free communities that previously did not.5 With these achievements come even greater challenges.