<h1>Diversion of chemical precursors requires enhanced international cooperation and intelligence-led measures to prevent illicit heroin manufacture.</h1> Diversion of chemical precursors used in illicit heroin manufacture, notably acetic anhydride, was identified as the central threat; experts reviewed trafficking trends and implementation of prior recommendations and prioritised strengthened regulatory and law enforcement controls across the precursor supply chain, the role of the private sector, and enhanced intelligence led operations and international cooperation. Consensual operational recommendations to improve information sharing, joint investigations and interdiction will be submitted to the Paris Pact Policy Consultative Group for approval.