Behaviour-centred design can be used to trigger changes in sanitation and hygiene practices. SNV Netherlands Development Organization used behaviour-centred design in an intervention to address the motivators of washing hands with soap in its Sustainable Sanitation and Hygiene For All (SSH4A) programme. This paper describes the use of emotional demonstrations (emo-demos) for triggering handwashing behaviour changes. The targets were the caregivers of children. Emo-demos focused on the motives of nurture (desire to care for one’s offspring) and disgust (a feeling of revulsion to avoid disease vectors and contamination). The paper provides practical information for implementing a small-scale handwashing promotion emo-demo within a WASH programme intervention. It concludes with lessons learned for wider practice.