In one way, the tasks of description, explanation, and optimization from their own sequence: If a team of developmentalists wants to understand their target phenomenon, first, they must discover and document its developmental course, including both quantitative and qualitative changes and periods of stability (i.e., describe the development of the phenomenon). Once its course has been charted, researchers can begin searching for underlying (or overarching) factors that produce these patterns of change and stability, working toward causal accounts of both normative development and differential pathways (i.e., explain the development of the phenomenon). Then when the explanatory network is sufficiently well-established, researchers can begin building interventions that target the creation of developmental conditions that support and maintain these explanatory factors (i.e., optimize the development of the phenomenon). In practice, research is more recursive, of course. Descriptive research suggests targets for optimization; experimental study of interventions can be used to identify causal factors; the analysis of explanatory factors suggests additional potential descriptive pathways; and so on. In fact, the active pursuit of all three of these tasks simultaneously characterizes the most generative research areas.