Ambiguity and Open-Endedness in Behavioural Design

Design is increasingly concerned with changing people’s behaviours. A common characteristic to behavioural design approaches is their directionality: products provide clarity about or guidance towards the designer’s intended behavioural outcome. In this paper we propose an alternative perspective that emphasizes ambiguity (i.e. affording multiple interpretations) and open-endedness (i.e. affording multiple courses of action). We build on two design cases in pediatric healthcare in which the aim was to stimulate young children’s physical activity during hospitalization. Instead of commonly used exercise-based approaches, our focus was on physical activity in the form of spontaneous and unstructured play. We describe how interactions with ambiguous and open-ended playthings gave rise to intended behavioural outcomes. The findings are explained by drawing on Activity Theory, suggesting products can direct and leave things open on different levels of interaction. With our contribution we open up a new design space for behavioural design that reconciles designer’s intentions with end user’s appropriation.