After two years of conflict, Yemen is facing a severe humanitarian crisis. An estimated 17 million people – 60% of the total population – are food insecure; at least 3 million people have fled their homes; and 11.3 million people need assistance to protect their safety, dignity or basic rights. This report provides information for aid agencies responding to the crisis to help them understand the operational threat context. It aims to prepare agencies for challenges they may face during the delivery of aid and support them in their work. It includes a breakdown of the type of security incidents reported in open sources and by partner agencies operating in Yemen. It shows the long-term threat patterns and provides updates on the most recently reported security incidents affecting the delivery of aid. All decisions made on the basis of or with regard to such information remain the responsibility of the organisations taking such decisions.