Developmental pathways to underage drinking emerge before the second decade of life. Many scientists, however, as well as the general public, continue to focus on proximal influences surrounding the initiation of drinking in adolescence, such as social, behavioral, and genetic variables related to availability and ease of acquisition of the drug, social reinforcement for its use, and individual differences in drug responses. In the past 20 years, a considerable body of evidence has accumulated on the early (often much earlier than the time of the first drink) predictors and pathways of youthful alcohol use and abuse. These early developmental influences involve numerous risk, vulnerability, promotive, and protective processes. Some of these factors are not related directly to alcohol use, whereas others involve learning and expectancies about later drug use that are shaped by social experience. The salience of these factors (identifiable in early childhood) for understanding the course and development of adult alcohol and other drug use disorders is evident from the large and growing body of findings on their ability to predict adult clinical outcomes. This review summarizes the evidence on early pathways toward and away from underage drinking, with a particular focus on the risk and protective factors and the mediators and moderators of risk for underage drinking that become evident during the preschool and early school years. It is guided by a developmental perspective on the aggregation of risk and protection and examines the contributions of biological, psychological, and social processes within the context of normal development. Implications of this evidence for policy, intervention, and future research are discussed. S EVERAL BASIC THEMES provide guidance for developing a perspective on the timing, processes, and experiences in earlier life relevant to the acquisition, use, and problem use of alcohol. First, much of the causal structure underlying youthful alcohol use and abuse is not specific to alcohol and in particular is either directly or indirectly the result of the development of externalizing and internalizing behaviors. 1-3 Family history of antisocial behavior, child maltreatment, and other negative life experiences are well-established precursors of later alcohol problems and alcohol use disorders (AUDs). These predictors are nonspecific risks for alcohol involvement, because they also predict a broad array of other problematic outcomes, including problems of undercontrolled or dysregulated behavior such as conduct problems, impulsivity, attention problems, aggressiveness, antisocial personality disorder, and depressive spectrum disorders.Second, at the same time that children develop behavior problems not specific to alcohol, they acquire knowledge about the existence of alcohol as an object in the social environment. Learning about alcohol includes developing beliefs about alcohol on the basis of an awareness of its special characteristics as a drug (how it produces changes in cognitio...