Over a career in research and policy, José Siri has developed and applied systems approaches to urban and planetary health, focusing on leveraging science for healthy development, devising simple systems tools to catalyze better decision-making, and improving understanding of complex challenges. His work has touched on urban studies, climate and health, sustainable development, systems thinking, transdisciplinary, epidemiology, ecology, infectious disease, public health, and malaria control. His experience, which spans five continents, includes time at the International Institute for Applied Systems Analysis, the United Nations University International Institute for Global Health, and the Wellcome Trust, and extensive engagement with researchers, practitioners, and policymakers. He has published over 30 peer-reviewed articles and book chapters, along with policy briefs and commentaries in publications ranging from the Wall Street Journal to the Global Sustainable Development Report. He is a member of the World Economic Forum Global Future Council for Cities, a co-founder of the Urban Health Research Network for Latin America and the Caribbean (LAC-Urban Health), and a Commissioner on the Tsinghua-Lancet Commission for Healthy Cities in China. He currently consults for the World Bank and the World Health Organization and holds advisory roles with the InterAmerican Institute for Global Change Research, Future Earth, CDP, and a variety of urban and planetary health research projects.