Professor Dennis Baldocchi is the quintessential biogeoscientist, with a stellar record of productive scholarly collaborations with scientists from around the world and unmatched mentoring of early-career scientists. He is a leader in running flux tower networks, serving as the science component leader and a member of science steering committees. He has forged productive collaborations among atmospheric scientists and ecologists, emphasizing positive mentoring and professional development for junior scholars. He has been the perennial mentor and keynote speaker for national and international workshops organized to train future professionals in flux tower studies, skillfully steering and inspiring generations of junior scientists. Throughout his career, he has sustained effective mentoring strategies with the view that the scientific community needs to rely on competent scientists from all cultural backgrounds. Baldocchi has commendably served the scientific community and national and international science advisory boards, including federal government funding agencies. He has been the editor of many journals, including the Journal of Geophysical Research: Biogeosciences, serving as its editor-in-chief.Baldocchi has been a transformative scholar. He conducted the first studies that merged rigorous plant physiological theory with atmospheric turbulence to provide early estimates of seasonal ecosystem-level assimilation of carbon dioxide. He launched research to demonstrate that in forested ecosystems, vertical canopy architecture and the surrounding microclimate are of paramount importance in estimating net carbon ecosystem exchange. His most creative thematic work involves extracting various timescale information about ecological processes from long-term flux monitoring records and exploring the interplay between ecosystem structure and function. Baldocchi pioneered the now-popular eddy covariance methods to estimate trace gas exchanges at the biosphere-atmosphere interface continuously for periods lasting years. Thanks to these innovations, scientists worldwide now pursue studies to understand how ecosystems respond to and mitigate climate change. Using data from flux tower sites globally, his research has been applied to project future carbon dioxide levels in the atmosphere. His scholarly work has enabled the solution of contemporary societal problems, such as providing baseline information on the role of terrestrial ecosystems in mitigating anthropogenic carbon emissions, thereby contributing to scientific and policy objectives.Overall, Baldocchi is an influential scholar in biogeosciences, unraveling the structural and functional complexities of plant ecosystems, explaining how energy and trace gas fluxes vary across a spectrum of temporal and spatial scales, and tirelessly promoting greater and more productive collaborations within and between the atmospheric science and ecology communities.—Jose D. Fuentes Pennsylvania State University University Park, Pennsylvania