Background: Approximately half of high school students in the USA have used tobacco. Social anxiety can put adolescents at increased risk for smoking. Purpose: This study aims to determine whether adolescents high in trait social anxiety report more cigarette use and greater urge to smoke before, during, and after friend interactions than do teens low in trait social anxiety. Methods: Four hundred two students who reported smoking more than once during high school were assessed approximately every 30 min during up to 84-day monitoring sessions. Results: Controlling for momentary anxiety, high socially anxious teens were equally or less likely to smoke, but more likely to report urge to smoke, surrounding friend interactions than low socially anxious teens. Conclusions: Although high socially anxious adolescents do not smoke more than low socially anxious peers, they may believe that they should need a cigarette in anxiety-provoking situations. Such urges may later develop into smoking behaviors. [ABSTRACT FROM AUTHOR]