Adolescent feelings of vulnerability, an aspect of the Health Belief Model and Elkind's concept of adolescent egocentrism, were examined in two groups of white, middle-class 6th to 12th graders. Feelings of vulnerability were examined with respect to developmental course, antecedents, and relationship to the specific risk-taking behavior of cigarette smoking. Feelings of vulnerability to the negative consequences of smoking were found to decrease rapidly from sixth to eighth grade and to increase slowly thereafter. Experience with illness and accidents was correlated with the general vulnerability measure. However, experience with illness due to smoking was not related to smoking vulnerability. This may have been because few adolescents were found to have had personal experiences with the health consequences of smoking. Feelings of vulnerability with respect to the negative consequences of cigarette smoking were correlated with adolescent smoking behavior. General feelings of vulnerability were unrelated to cigarette smoking.