As psychiatric genetics enters an era where gene identification is finally yielding robust, replicable genetic associations and polygenic risk scores (Okbay et al., 2016, Schizophrenia Working Group of the Psychiatric Genomics Consortium, 2014), it is important to consider next steps and delineate how that knowledge will be applied to ultimately ameliorate suffering associated with substance use and psychiatric disorders. Much of the post-GWAS discussion has focused on the potential of genetic information to understand the underlying biology and use this information for the development of more effective pharmaceutical treatments. While this is clearly an important goal, it is not the only one. By taking genetic findings into longitudinal, developmental studies, we can map the pathways by which genetic risk manifests across development, elucidating the early behavioral manifestations of risk, and how various environments and interventions moderate that risk across developmental stages. Here we have reviewed studies that suggest these are important avenues for exploration, and we provide examples of studies that have begun to address these kinds of questions. We note that these new areas of study will present their
