Celebrating the legacy and work of John Schulenberg: Answering the question "Does adolescence matter?".

Dr. John Schulenberg (1957-2023) was a brilliant and internationally recognized developmental scientist. In equal measure, he was an outstanding, dedicated, and generous mentor. Through his scholarship and mentorship, his impact on the fields of adolescent and substance use research will be deep and enduring. The overriding theme of his research was illuminating the importance of adolescence in the life course, which he referred to as "Taking the Long View" on adolescence. John's longstanding motivation for this was to answer the question: "Does adolescence matter?" This special issue, which (in addition to this introduction) includes 14 papers and 2 invited commentaries, is designed to honor his scholarship and impact. For this introduction to the special issue, we divide what it means to "Take the Long View" on adolescence into four major themes: (1) Turning points; (2) Developmental disturbances; (3) Continuity and long-term developmental connections; and (4) Heterogeneity in the age curve. We describe these four themes, consider how they connect with the overarching question "Does adolescence matter?," and discuss how the research papers included in this special issue are excellent examples of research inspired by these themes.