Project Summary (Abstract) This is a basic science training grant focused on an integrative understanding of post-natal human behavioral development. The rationale for the focus on integrative training is that effective translation requires more than merely rapid movement of single-variable basic science findings to efficacy studies but a different basic science, one that embraces complex causal pathways of development, and considers processes at nested time scales and multiple levels of analysis. The training program focuses on behavioral development (and relations to brain development) because advancing research shows that post-natal behavior and the experiences generated by that behavior modulates both structural and functional connectivity in the brain, tunes specialized neural systems and influences gene expression, with atypical patterns of early behavior and experiences determining the quality and opportunities of whole lifetimes. The trainees are 5 predoctoral candidates in psychology and in two joint PhD programs in psychology and neuroscience and in psychology and cognitive science and 3 post-doctoral fellows from various fields interested in developmental process. The training program for pre- doctoral trainees is 5 years (with 2 years supported by the training grant and 3 years by the department of Psychological and Brain sciences); the training program for post-doctoral trainees is typically 2 years. All trainees are required to submit at least one grant (foundation, F31, F32, or NSF) while affiliated with the program. The training program emphasizes the use of cross- levels methods to study the same problem, basic science that can link to translation, the collection and analysis of large data sets, open data and data sharing, and the ethical conduct of research.