Introduction With the COVID-19 vaccination process underway, employers are navigating unprecedented issues within their workforce. This article explores, among other things: employers' obligations when implementing mandatory vaccination programmes; issues concerning employee data that is provided as proof of vaccination or pre-vaccination screening; and defining 'reasonable accommodation' and potential Americans with Disabilities Act (ADA) concerns.(1) Employers' obligations when implementing mandatory vaccination programmes Employers that implement mandatory COVID-19 vaccination programmes should pay close attention to their responsibilities under the following as many of the traditional applications of these laws apply to this type of programme: Title VII of the Civil Rights Act;