To reflect the complexity of alcoholism and the heterogeneity of the alcoholic population, an etiologic model should integrate biological, psychological, and environmental factors. The model proposed here does so, postulating that "risk" for alcoholism fluctuates throughout the lifespan of an individual. In addition, this developmental ecological model takes into account both the imputed risk and the protective factors, makes possible a more detailed analysis for each life stage of an individual, and remains flexible enough to accommodate forthcoming empirical data.