Commentary Vaccination passports certify that holders are immune from the virus causing COVID-19 through vaccination, or the presence of antibodies caused by earlier infection. These passports are widely expected to ease and speed the transition from the current pandemic to normal personal and economic lives but have encountered some public and political opposition. There’s no doubt that presently the number of Canadians eligible to receive the passport is large. On May 3, 2021, 12.9 million Canadians had been immunized and 1.14 million had recovered from the illness. Their numbers are growing rapidly with new vaccinations and recoveries. The problem with current discussions about the merit of the passports is that there’s no single, detailed model of how a passport system would operate. As a result, much controversy and opposition is based on features that may or may not be adopted but which could be avoided by considering this simple model. Passport holders have access …