PURPOSE. This Advisory Circular (AC) provides guidance to Airlines to operate safely post COVID-19 lockdown. It aims to address the following concerns:  When sending crew on international flight operations, how do we prevent them from: - Transmitting the virus amongst themselves? - Contracting COVID-19 when they are staying abroad during a layover, and - Importing the virus when they return?  When allowing foreign crew to enter Nigeria, how do we: - Prevent foreign crew from transmitting the virus to the local community and creating new clusters of transmission, and vice-versa? - Manage foreign crew when they exhibit symptoms of COVID-19 on arrival or develop symptoms during layover?