We have created an evidence-based guide for clinicians to the relative utility of nonpharmacologic treatments for attention-deficit/hyperactivity disorder (ADHD). This article uses the term evidence-based in the sense applied by the Oxford Center for Evidenced-Based Medicine to help readers understand the degree to which nonpharmacologic treatments are supported by the scientific literature. This article also reviews the magnitude of the treatment effect expressed as the standardized mean difference effect size (also known as Cohen D). It then describes a meta-algorithm to describe how to integrate pharmacologic and nonpharmacologic treatments for ADHD.