1) The webinar discussed building the BESSI collaboration to address COVID-19 and future outbreaks through interdisciplinary behavioral, environmental, social and systems interventions (BESSI). 2) A survey of 50 participants from 18 countries found most worked in psychology, public health, and epidemiology and were interested in behavioral and systems interventions. 3) Building the collaboration will require identifying global members, building research capacity worldwide, engaging knowledge users, finding early successes and funding, and encouraging interdisciplinary work across communities. Governance structures and communication tools are also needed.