COVID-19 symptoms can persist in an estimated 10% of patients long past recovering from the worst impacts of acute infection and testing negative for SARS-CoV-2. Inconsistencies in symptoms, patient phenotypes, and risk factors make it difficult to pinpoint the exact cause of Long COVID. In this issue of Cayman Currents, explore prominent theories of underlying pathophysiology, lessons from other post-viral syndromes, and Cayman’s products and services to accelerate Long COVID research.