Depression usually has its onset during adolescence or early adulthood. Recurrences are common and contribute to its substantial disability. Mild symptoms may be the beginning of a new episode or lingering consequences of a partially remitted episode. Waiting for symptoms to become full blown or leaving mild symptoms untreated may miss opportunities to improve patient outcome. An understanding of the natural course of untreated depression, together with an appreciation of differences between clinical research and practice, facilitates translation of research findings into effective clinical care.. Login at top right hand side of page using your MPFT NHS OpenAthens for full text.