Researchers from Yale School of Public Health used a previously published model of a COVID-19 vaccination program to quantify the speed-versus-efficacy tradeoff of vaccination deployment. The model accounted for transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), COVID-19 disease severity, and recovery or vaccination leading to protective immunity. According to the authors’ analysis, a 2-dose vaccination strategy would impose steep clinical and epidemiologic costs in the context of ongoing pandemic response. Depending on the duration of protection conferred, a single-dose vaccine with 55% effectiveness may confer greater population benefit than a 95%-effective vaccine requiring two doses.