Just as the brain changes over the life course to meet unique challenges and make new discoveries at each developmental phase, so too is the field of cognitive neuroscience changing. Over the years, we have seen significant advances in neuroimaging techniques and computational analytics as well as an enormous expansion of open-access data and tools that have broadened the reach of cognitive neuroscience to neighboring fields and broader society. This lecture will highlight how advances in cognitive neuroscience have informed our understanding of how the mind and brain develop and examine how this knowledge informs the treatment of the developing mind and brain in medicine and in the U.S. legal system.