Direct observation is often considered the "gold standard" for assessing the function, frequency, and intensity of problem behavior. Currently, the literature investigating the construct validity of direct observation conducted in the clinic setting reveals conflicting results. Previous studies on the construct validity of clinic-based observations of parent and child interaction have focused on correlating behavior rates across clinic and home settings. These studies provide some preliminary data on how accurately in-clinic observations reflect the rates of behavior in the home setting; however, they provide little information regarding the interaction patterns between the parent and the child. The current study explores a method of assessing construct validity by comparing parent-child interactions in the clinic with parent-child interactions in the home. Results of this investigation suggest parents and children may exhibit similar rates of behavior in the clinic and home during structured activities and similar types of interactions during those activities. (Contains 5 tables and 8 figures.)