As businesses and offices around the province slowly reopen, contact tracing is being signalled as the next frontier in battling COVID-19. And as social interactions increase, so does the need to track those interactions. Painstakingly following people, and potentially the virus's movement involves thousands of investigators. Ashleigh Tuite, an epidemiologist at the Dalla Lana School of Public Health; and Nancy Bevilacqua, a public health official and contact tracer at York Region Public Health, discuss how it all works and how Ontario has been doing?