The difference between incremental learning and true discovery is surprise. The history of science is rich with examples of discoveries promoted by serendipity, notable among them, ionizing radiation, the role of DNA in inheritance, the connection between magnetism and electricity, and the Theory of Evolution. The central theme of this organized session is that long-term research can exploit the arrival of novel, disruptive, surprising observations to enable discovery, observations that in short term studies would probably been seen as a nuisance. However, the occurrence of unanticipated events without the proper research context creates more confusion than insight. A research context capable of benefiting from surprises involves three essential elements. Researchers must be sufficiently familiar with the system they study and with the predictions of contemporary theory to recognize observations that are exceptional, observations that are capable of producing new, perhaps transformed understanding. Investigators must have sufficient predictability and continuity in funding to allow them to pursue new observations, observations capable of distinguishing unexpected events from truly stochastic ones. And finally, surprises in ecological studies can be exploited only if they occur within studies conducted with thoughtful design, guided by question-driven research. In this session, we proposal to highlight a diverse array of long-term ecological studies, from marine, to terrestrial, from the subtropics to the arctic tundra, that demonstrate examples of the value of surprises in long-term studies, the discoveries surprises promoted, and the research context that was required to exploit them. This is becoming especially apparent in the era of unprecedented global and climate change, and in addressing the themes of the entire conference of linking biodiversity and ecosystem services. We emphasize that long-term monitoring by itself is not necessarily sufficient to design effective long-term research on ecological phenomenon, and illustrate throughout our symposium the benefits of marrying question-driven ecological research with long-term investment in research. In this symposium, we draw together 10 leading researchers who received funding for their decadal research through the National Science Foundation’s Long-term Research in Environmental Biology (LTREB). With an opening introduction by the recently retired long-term LTREB program manager, Saran Twombly, the session aims to conduct a retrospective evaluation of the past decades of research with a prospective vision for the future of investment in long-term research in ecology and environmental biology.