Behavioral UX Design Has an Ethics Problem

Behavioural design in sustainability tech is powerful and underexamined. The article argues that designing to change people's behaviour, even toward genuinely good outcomes like reducing plastic or returning reusable cups, carries ethical responsibilities that positive intent alone doesn't resolve.It names three tensions designers in this space routinely face: engagement versus transparency, impact communication versus impact inflation, and user benefit versus data extraction. It then offers a practical four-question framework any designer can apply to their own work, a dedicated section of concrete Monday-morning steps, and a forward-looking warning about AI-personalised nudges raising the stakes further.The piece closes with a clear position: the most effective behavioural design over time is the kind that respects users enough to tell them the truth.