Adverse psychosocial outcomes can be anticipated among youth exposed to Hurricane Katrina. Adolescents are particularly vulnerable to the consequences of this natural disaster and may suffer lasting consequences in the form of psychological morbidity and the development of negative health behaviors due to their exposure. We review existing literature on the effects of exposure to natural disasters and similar traumas on youth and, where data on youth are unavailable, on adults. The effect of natural disasters is discussed in terms of risk for three negative health outcomes that are of particular concern due to their potential to cause long-term morbidity: post-traumatic stress disorder, substance use disorder, and HIV-risk behavior. Where available, data from studies of the effects of Hurricane Katrina are included.