This study describes the reported observations of protective services workers who varied in the accuracy with which they could discriminate abusive from nonabusive mother-child interactions. Participants viewed videotapes of two abusive and two nonabusive dyads. They noted behaviors that suggested an abusive history and behaviors that suggested a nonabusive history for each dyad. Comparisons of more and less accurate judges indicated that accurate judges observed more evidence for abuse when the dyad actually was abusive. The informational advantage of experts was not limited to detecting interactional difficulties in abusive dyads; they also reported observations of more favorable behaviors of nonabusive dyads. Highly accurate judges were more likely to observe communication patterns, task-oriented behavior, and other-directed behaviors than were less accurate judges. These findings suggest that specific information-processing factors may vary with clinical expertise.