Social norms are rules that prescribe and proscribe behavior. The application of norms is conditional. But scholars have little systematic understanding of the factors that affect conditionality. The authors argue that understanding norms requires assessing the costs and benefits of focal and nonfocal behaviors for norm targets, beneficiaries, and enforcers. The authors develop hypotheses about two combinations of these factors; they hypothesize that 1) costs to the norm target of complying with the norm, and 2) behavior by the norm beneficiary that hurts the norm target, weaken the norm. The authors use a vignette experiment to test these hypotheses in the context of bridewealth norms in Africa. The results are consistent with the predictions. The study contributes to the literature on norms by suggesting a systematic approach to understanding norm conditionality.