Abstract: The main goal of the First European conference on drug supply indicators was to launch the work needed to establish a set of technically sound and sustainable indicators for monitoring drug markets, crime and supply reduction for Europe. The event brought together for the first time a wide range of European and international experts to assess the current state of the art in this domain and develop a realistic strategy for moving forward in an area of importance for European drug policies. The conference was a joint venture between the European Commission (EC) and the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) with the active involvement of Europol. The key conclusions from the event are presented in this document.