This report describes at a high level what a model regulatory regime for harm reduction in social media that respects freedom of expression in the European tradition might look like. The regime we propose is not a silver bullet – it will not solve all internet-related problems. As we shall explain, however, a statutory duty of care enforced by a regulator can provide a solid foundation for more detailed rules or interventions to target specific circumstances; it does not exclude the possibility of other measures (e.g. media literacy and ethics training) being used as well.