The World Health Organization has updated their interim operational guide for maintaining essential health services during an outbreak, to support countries preparedness and response during the COVID-19 pandemic. It supplements existing and future WHO guidance on the wider implications of COVID-19 for health systems, and cross-government strategies for responding to the COVID-19 outbreak. The updated guidance has two parts: operational strategies for maintaining essential health services; and life course and disease considerations. As an annex, the guidance includes sample indicators for monitoring essential health services.