The WHO’s Private Sector Engagement COVID-19 Initiative (WHO-PCI) case study series is for Member States seeking to engage the private health sector in their COVID-19 response. The series seeks to promote a culture of “learning by doing”, recognizing that necessity and urgency are producing examples of private sector engagement. As the COVID-19 context is dynamic, this series will be periodically updated with emergent practice. A draft private sector engagement strategy has been developed and provides further guidance on governance of mixed health systems.