This paper focuses on the development and meaning of informal social control experiences when strangers intervene face-to-face in instances of child punishment in public. The central question is, in the absence of formal authority and institutional resources, how do strangers construe wrongful punishment, negotiate deviant import, and manage control outcomes? Thirty-seven interviews were conducted with people who intervened on at least one occasion, and seven more with witness-participants. Interviewees described the meanings, events, and circumstances surrounding 50 acts of face-to-face intervention. The analysis focuses on some of the micro-political forces, such as claim themes and audience norms, that shape control outcomes. The interpersonal predicament for interveners reflects the cultural tension created when approval of physical punishment is widespread, when distinctions between normal and deviant punishment are ambiguous, and when interaction rules for informal intervention are not institutionalized.