Healthy markets cannot be based simply on what is technically legally permissible. Something more is needed, variously described as ‘culture’, ‘professionalism’, ‘ethics’ and ‘morality’: the Governor of the Bank of England has used the expression ‘social licence for financial markets’. This chapter explores what the substance of such a licence might be. Among other things, by using a ‘written standards map’ of financial sector laws, rules and codes of practice, it considers the extent to which each category of written standards could be thought of as being part of a social licence; how they might express the substance of a social licence and how they might help to realise its aspirational dimension. It identifies what appears to be both substantive and aspirational common ground between the idea of a social licence and written standards directed at financial market participants, especially in the case of written standards that operate by reference to other-regarding values. Both seem to concern the pursuit of just ends by just means in financial markets. The chapter concludes by briefly highlighting some of the implications of this.