Christine Regalla has made significant contributions to our understanding of convergent margins. Her work on the Japan, Nankai, Cascadia, and Alaskan subduction zones represents an extraordinarily broad research footprint for her career stage, exemplifying her multidisciplinary approach and transdisciplinary impact. Her work on the Japan Trench challenged the paradigm that the margin is “erosional” by integrating onshore geological field and lab studies to propose that the forearc subsidence previously inferred to have been driven by basal erosion is instead due to changes in plate motion rates that propagated significant structural responses through the subduction system. By integrating processes that act across plates and incorporating the coupling between different spheres of Earth’s system (e.g., tectonic processes, global climate change, sea level changes), she has developed a unique “subduction system science” approach that sets her work apart from her peers. Sailing on Expedition 343 (Japan Trench Fast Drilling Project (JFAST)), she applied her knowledge and expertise to interpret the site survey seismic reflection data and to provide insight into the structures recovered in the JFAST cores. She also demonstrated how the hazard from huge earthquakes extends into the onshore region through reactivation of forearc faults. She applied a novel geochronological technique to the frontal prism cores to define and explain the megathrust processes and how these result from interactions between the subducting and overriding plate. Her astute interpretation shows that sediment thickness and outer-rise fault throw are important controls on shallow megathrust behavior. The depth and breadth of Christine’s contributions led to her selection as co–chief scientist for Expedition 405 (Tracking Tsunamigenic Slip Across the Japan Trench (JTRACK)). Her leadership and scientific vision contributed significantly to developing and implementing a targeted operational design, making Expedition 405 a huge success. From preexpedition planning to onboard real-time decision-making, she led the way during the expedition. Christine’s research career has thus followed a remarkably similar path to Asahiko Taira’s: During her early career, she developed a strong field geology background for understanding tectonic/structural processes, then sailed on multiple ocean drilling expeditions, collaborating with scientists at all levels from around the world to investigate modern subduction processes, then adding analysis of marine geophysical data to extrapolate drilling results broadly. These collaborations have enabled Christine to investigate subduction zone processes that occur over a wide range of temporal and spatial scales, and her multidisciplinary approach has elevated her research to have broader impacts than typical for purely expedition-based research. —Gregory Moore, University of Hawai`i, Honolulu, Hawaii