Friman, Patrick - Interpreting common child behavior problems as evidence of psychopathology is routine in mainstream psychology. The practice is so widespread that when investigators fail to obtain clinically significant levels of behavior problems, as indexed by standard scores on assessment instruments, they usually (almost always) reanalyze their data in terms of raw scores and then argue that any statistically significant elevation is evidence of pathology. Four representative common child behavior problems are encopresis, enuresis, thumb sucking, and hair pulling and psychopathological interpretations of each are easy to find. Three of the most common tests of psychopathology are: 1) clinically significant levels of co-occurring behavior problems; 2) resistance to direct treatment; and 3) symptom substitution. An abundant amount of research shows that each of the four representative behavior problems fails all three tests. Two possible reasons for the existence and persistence of the psychopathology interpretation, despite readily available data to the contrary, are Berkson’s and textbook case biases. Berkson’s bias involves the influence data obtained from hospitalized subjects with compound problems has on the interpretation of isolated problems in outpatient or nonreferred subjects. Textbook case bias involves textbook reliance on complex, resistant, multiproblem cases for teaching while the majority cases are simple, responsive, and involve relatively isolated problems. Regardless, the routine interpretation of child behavior problems as pathology presents an enormous opportunity for behavior analysis. Specifically, most parents of children with common behavior problems are reluctant to seek professional help from clinical psychologists and psychiatrists, due in no small way to their aversion to the pathological view. Because the conceptual framework for behavior analysis does not include a pathology construct, behavior analysts could focus on the assessment and treatment of common child behavior problems and potentially capture a virtually unlimited market for their services.