The 18th Smithsonian Botanical Symposium, co-hosted by the Smithsonian’s Department of Botany and the United States Botanic Garden, was held virtually over two days on May 13 and 14, 2021. The Symposium, “Plant symbiosis: The good, the bad, and the complicated,” was originally scheduled to take place in May 2020 at the National Museum of Natural History (NMNH) in Washington, DC, but the coronavirus global pandemic pushed the symposium to 2021. The digital event this year successfully brought together six engaging speakers in a Zoom webinar setting to explore current research in the diversity of plant symbioses, examining the relationships plants have with insects, fungi, bacteria, and even other plants. Invited speakers included botanists, ecologists, microbiologists, and geneticists whose research unravels the complicated relationships that plants have with their collaborators and competitors in the natural world.

All speaker presentations, opening remarks, the presentation of the Jos? Cuatrecasas Medal, and the roundtable panel discussions were recorded and are available for viewing at NMNH's Natural History for Scientists YouTube.