Over the past decade, there has been an enormous increase in research and scientific publications targeting psychological resiliency. However, compared to the research on the neurobiology of stress, resiliency research is in its relative infancy. Much of the resiliency research has focused on theoretical models and the conceptualization of psychological resiliency. Resiliency research has been limited by (1) the broad use of the term resiliency; (2) the lack of standardized definitions of resiliency; (3) a primary focus on descriptive, assessment, and measurement studies; (4) relatively few randomized controlled trials to evaluate the efficacy of resiliency enhancement programs; and (5) methodological challenges inherent in conducting applied resiliency research. Although many recent programs have been initiated in attempts to enhance psychological resiliency in targeted populations, such as military personnel, relatively few randomized controlled trials have been conducted. Translational research, prospective longitudinal cohort studies, and clinical intervention trials are needed to better understand the behavioral neurobiology of stress and psychological resiliency.