There has been an unprecedented global effort by researchers from many disciplines to obtain and synthesize knowledge to inform policy responses to SARS-CoV-2. While many major advances have been made in generating and applying knowledge on a pandemic caused by a novel pathogen, some things could have been done better, as revealed by the devastating loss of life and economic impact on livelihoods and communities. We reflect on the context in which the pandemic emerged, characterized by underinvestment in public health and growing distrust in institutions, followed by an overview of three broad areas: generation of new knowledge, synthesis of existing knowledge, both what was known prior to the pandemic and what emerged during it, and the challenges of translating knowledge into policy. We also consider areas that were largely overlooked in the research effort. Across all areas, we aim to draw out relevant lessons for future research and public health practice.