This is a collection of original articles on diverse vulnerable populations in Japan in the wake of the new coronavirus pandemic. The effects of COVID-19 are felt differently, with some among us at much greater risk of infection due to preexisting health and welfare conditions. For others, perhaps more than the risk of infection, it is the precautions taken to mitigate the risk for the whole population, such as lockdowns and business closures, that have pulled away the already fragile safety net of state and civil society organization (CSO) support, leading to increased marginalization and social exclusion. The goal of this set of papers is to document the conditions of those that have been most directly affected by the virus and to provide background on the conditions that made them vulnerable in the first place, notably chronic conditions that are brought into more obvious relief in light of emergency measures. Each of the authors had a pre-established relationship with those affected populations and employed various ethnographic approaches, some face to face, others digitally via Zoom interviews and SNS exchanges. In this moment of what appears to be relative calm, we hope that our collection, quickly compiled in an attempt to capture the ever-changing situation, will give some insight into how those most vulnerable are faring in this time of crisis and provide information that will allow us to prepare better before the next wave comes our way.