Australia's national living guidelines for COVID-19 were launched in April 2020 and include over 200 recommendations to guide the clinical care of patients with COVID-19. Until the guidelines were retired in August 2023, new evidence was continually monitored through daily surveillance. This paper describes the initial design for evidence surveillance (at a time when efforts to collate information on the novel coronavirus were in their infancy and often duplicative) and how it was refined throughout the pandemic. Among the wide range of sources monitored, the collections of COVID-19 research from leading medical journals, medRxiv preprints and PubMed auto alerts proved the most enduring in identifying time-critical and impactful evidence. The paper also explores how evidence was tracked and surveillance integrated into the overall evidence workflow by using messaging apps and communication platforms. Finally, we consider the implications for living guidelines and reflect on factors that contributed to the feasibility of daily surveillance: the clearly defined scope of the guidelines; focusing efforts on maximum impact; minimizing duplication by partnering with others; setting up simple but effective processes for managing evidence; and the value of continuous involvement of personnel from the outset. Australia's living COVID-19 guidelines were underpinned by a novel approach to evidence surveillance that was feasible and essential in maintaining COVID-19 living guidelines for over 3 years.