The goal of optimization of human development refers to research and intervention activities designed to figure out how to promote healthy development (also referred to as flourishing or thriving) and the development of resilience. This task goes beyond description and explanation in two ways. First, in order to optimize development, trajectories and pathways must be identified as targets—targets that represent “optimal” development. These kinds of trajectories are often better than normative development, and so represent rare or even imaginary pathways, especially for groups with many risk factors. The search for optimal pathways reflects the assumption that individuals hold much more potential and plasticity in their development than is typically expressed or observed. The second way that optimization goes beyond description and explanation is that even when explanatory theories and research have identified the necessary and sufficient conditions likely to promote optimal development, researchers and interventionists still need to discover the strategies and levers that can consistently bring about these developmental conditions. For example, suppose that in studies of motivational development, researchers have uncovered multiple factors that are important to promote student engagement, such as teacher autonomy support, authentic academic work, school climates organized around mastery-oriented learning goals, parent investment in student academic success, and student self-efficacy. These would all be potential candidates for inclusion in interventions to optimize motivation. However, from such research, interventionists have no clues as to the strategies that will allow them to effectively (and permanently) change those developmental conditions. One way to understand the difference between explanation and optimization is that, if explanations focus on the antecedents of a developmental phenomenon, then optimization efforts need to focus on the antecedents of these antecedents.