Will Tokyo 2020 pay off for the host-city or will they result in economic losses? The answer to this important question is a matter of belief. It is based on assumptions about what would have happened if Tokyo had not hosted the Games. Depending on assumptions, cost estimates for Tokyo 2020 vary from $5.2 to $28.1 billion and benefit estimates from $64 to $155 billion. Assessments of the overall economic impact range from $36 to $220 billion. However, if the Olympics can rejuvenate the ageing society and economy, the benefits will indeed be huge, though not easily expressed in numbers.