This session honors the contributions of Daniel Simberloff, one of ESA’s distinguished scientists, in developing key ecological theories that have shaped how we study and manage ecosystems. Over the past five decades, Simberloff has injected diverse, influential, and sometimes controversial ideas into many subfields of theoretical and applied ecology, including island biogeography, species-area relationships, community assembly, species coexistence, null models, conservation biology, and invasion ecology. One characteristic that is a trademark of Simberloff’s career is his unwavering insistence on the primacy of empirical evidence and the cautionary interpretations of limited data. Simberloff has eloquently and ardently advocated for researchers to embrace and appreciate the complexity of ecological systems. To that end, he champions local experimental studies that reveal the natural history and informative contingencies that each unique species assemblage and ecosystem offers. Remembering and heeding this cautious voice is of critical importance as ecologists “harness the ecological data revolution”. While these big and diverse datasets will allow ecologists to address the most pressing ecological and environmental questions at the global-scale, a key challenge will be retaining and incorporating the importance of the ecological complexity of local systems. Here, we bring together a group of diverse scientists that will reflect upon Simberloff’s contributions to ecology. Each talk will focus on a key subfield of ecology where Simberloff’s contributions have shaped the current state of the field. The talks will not only celebrate Simberloff’s accomplishments but also examine how his ideas on have contributed to the development and advancement of the current and future state of the science. Collectively, the session will illuminate and frame key questions for future research in ecology, provide inspiration and insight for early-career researchers, and highlight the importance of integrating theoretical and applied ecology to better understand and manage Earth’s species and ecosystems.