The purpose of this study was to examine racial/ethnic differences in adolescent smoking behavior, sources of tobacco, knowledge of and attitudes toward youth tobacco restriction policies, and perceptions of tobacco availability by adolescents. The study is important as it will add to the growing body of literature regarding tobacco use by minors, and will help policymakers and public health professionals develop efficacious policies and interventions to prevent and reduce tobacco use among adolescents. Minors obtain tobacco from social and commercial sources. Previous studies have emphasized rural homogeneous populations and so the present study addresses the need to determine these sources of tobacco to youth in a large urban, heterogeneous population, such as Philadelphia. A stratified multistage purposive sampling procedure was used to ensure an ethnically/racially sample. A 68-item questionnaire was administered to 645 students in Grades 8-10 in five public and nonpublic funded schools in a culturally diverse part of Philadelphia. Correlations between selected independent variables and smoking behavior were determined. Results from this study indicate that rates of smoking are high among students, with 50% of students ever having smoked, 19% within the last month, 17% weekly, and 15% smoke daily. Further, there were differences in rates of smoking between ethnic/racial groups. Social sources were the most common sources of tobacco reported, with friends being the most frequent source. There were differences in social and commercial ever sources of cigarettes between ethnic/racial groups and in perceived school and parental sanctions for tobacco use. The results of this study suggest that more financial and educational resources should be committed to prevent and reduce smoking behaviors among adolescents. Educational prevention programs, especially parenting programs should be employed to reduce smoking.