MOSAIC is a health economic modelling collective established to provide rapid policy guidance and public engagement for the South African Covid-19 response. Members are drawn from the Health Economics Unit, School of Public Health and Family Medicine and Alan J Flisher Centre for Public Mental Health at the University of Cape Town, with the Health Systems Research Unit at the Medical Research Council. In alphabetical order, MOSAIC includes Donela Besada MPH; Susan Cleary PhD; Emmanuelle Daviaud MSc; Sumaiyah Docrat MPH; Darshini Govindasamy PhD; Geetesh Solanki DrPH; Cynthia Tamandjou PhD; and Tommy Wilkinson MSc.