Humanitarian crises are politically and socially charged, and as actors, donors and organizations move in to help, duplication of services can ensue. Despite the influx of humanitarian actors into the war zone of eastern Ukraine, more are still needed to address immediate threat to the health of more than 5 million at-risk people in the area. The humanitarian disaster in Ukraine requires fast support and stakeholder involvement to mitigate preventable death among at-risk populations. As the crisis unfolds and many more people are caught in the crossfire with no health security, WHO is leading the charge to organize healthcare and humanitarian action to relive human suffering and engender health security for all.