Many college students are using substances at levels consistent with Substance Abuse or Dependence, yet little explanation for this phenomenon exits. The aim of this study was to explore a risk factor profile that best separates those with low and high potential for having a Substance Use Disorder (SUD). A discriminant function analysis revealed that participants with a high probability of having a SUD misperceive others' alcohol and marijuana use to a greater extent than those with a low probability of having a SUD. Implications for educators and counselors on college campuses are discussed. (Contains 2 tables.)