One fundamental function of social norms is to promote social coordination. Moreover, greater social coordination may be called for when tight norms govern social relations with others. Hence, the sensitivity to social norm violations may be jointly modulated by relational goals and a belief that the social context is tight (vs loose). We tested this analysis using an electrocortical marker of norm-violation detection (N400). Ninety-one young American adults were subliminally primed with either relational or neutral goals. Then they saw behaviors that were either norm-violating or normal. In the relational priming condition, the norm-violation N400 increased as a function of the perceived tightness of societal norms. In the control priming condition, however, the norm-violation N400 was weak regardless of perceived tightness. Thus, normative tightness was associated with increased neural processing of norm violations only when relational goals were activated. Implications for norm psychology are discussed.