Why and under what conditions are the state's regulations complied with, and when are they violated? Resource scarcity and strict regulation of the Atlantic fisheries have generated a demand for in-depth knowledge of this issue. This comparative study is based on qualitative data from Norway and Newfoundland. It shows that informal social control is a major factor inhibiting violations of formal management regulations among fishermen, and it analyses the relevant moral norms and how they influence compliance. It addresses the relationship between collective morality and self-interest, and describes combinations of normative and strategic action. The comparison of the cases ends with a general theory on the morality of compliance in economies based on harvesting of natural resources for households as well as the market.