 Recent epidemiologic, virologic and modeling reports support the possibility of severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 transmission from persons who are pre-symptomatic SARS-CoV-2 detected before symptom onset or asymptomatic SARS-CoV-2 detected but symptoms never develop. SARS-CoV-2 transmission in the absence of symptoms reinforces the value of measures that prevent the spread of SARS-CoV-2 by infected persons who may not exhibit illness despite being infectious. Critical knowledge gaps include the relative incidents of asymptomatic and symptomatic SARS-CoV-2 infection, the public health interventions that prevent a symptomatic transmission, and the question of whether a symptomatic SARS-CoV-2 infection confers protective immunity. This article was authored by Nathan W. Furukawa, John T. Brooks, and Jeremy Sobel.