The National Center on Addiction and Substance Abuses surveys have consistently found that the family is fundamental to keeping children away from tobacco, alcohol and illegal drugs. This 2002 survey keeps the focus on family and seeks to assess the impact of siblings on the likelihood of teen substance abuse. This year 1,000 teens ages 12 to 17 and 541 parents were surveyed. The most striking conclusions are these: for the first time, a majority of teens attend drug-free schools; siblings have a major impact on substance abuse risk; for the seventh survey in a row, teens continue to say drugs are their biggest concern; for the first time, a higher percentage of teens surveyed finds marijuana easier to buy than both cigarettes and beer. The take-home message of this survey is that to prevent our teens from substance abuse, we need to bolster their will and skills to say no before age 12. The reality is that for most teens, high school--and often middle school--is too late to begin. Parents, teachers, school administrators and public policymakers must focus their attention on inoculating kids against all drugs in the early years before exposure occurs. Five appendixes present sample performance, survey methodology, screening questions, and data. (GCP)