This study was designed to investigate whether a brief intervention encouraging parental coping-promoting talk within the treatment room would have beneficial effects on infant pain responses to an immunization injection. Infant-parent dyads were recruited from a 6-month immunization clinic and randomized to an intervention group (n = 25) or standard care control group (n = 25). Parents in the intervention group received an information sheet describing adult verbalizations associated with better pain outcomes for infants. The immunization procedure was videotaped. Parents in the intervention condition made significantly more coping-promoting statements than parents in the control condition. Infants in the control condition cried significantly longer than infants in the intervention condition. Coping-promoting and distress-promoting statements did not differ in terms of affective quality. Infants whose parents had rated them as more difficult in temperament cried longer following the injection. Teaching parents to engage in coping-promoting behaviors within the infant treatment room is an effective, low-cost intervention.