Patients exhibiting symptoms associated with conduct disorder present challenges in assessment and treatment. The difficulties are not only the complexities of correct identification and appropriate intervention, but also that the knowledge is rapidly growing. Evidence-based practice (EBP) provides a useful framework for dealing with these issues. In the assessment of antisocial behaviors, EBP assists in the often complicated consideration of differential diagnosis and the frequent presence of comorbid conditions. The EBP approach of developing specific clinical questions is also useful in evaluating treatment options for the myriad symptoms of this heterogeneous disorder. A practitioner can easily feel overwhelmed when trying to keep up with new research. EBP is a practical method for sifting through the current literature. This article illustrates the application and utility of EBP with antisocial behaviors as shown in the assessment and treatment of "Evan," a 10-year-old white boy with a bullying problem. (Contains 1 table.)