Environmental crime is on the rise and is of growing concern to policy makers, to legitimate businesses, and more broadly to the general public. It is growing rapidly worldwide on average at over 8% per year, with an estimated value between USD 110-281 billion in 2018. Emerging issues include wildlife trafficking, illegal timber, illegal mining, illegal chemicals, illegal waste trafficking, and illegal, unreported and unregulated (IUU) fishing. Environmental crime can have serious implications to human health and the environment, to the global economy, and more broadly to good governance, national security and sustainable development. Addressing these criminal activities affecting the environment is difficult exclusively at the national level as they often extend on a transnational scale. In this context, this report provides a snapshot of cross-border environmental crime and available initiatives to tackle illegal activities at a transnational scale, with a particular focus on multilateral and regional frameworks. The key message from this report is that the increasing prevalence of cross-border environmental crime is due to regulatory failures and the growing involvement of transnational organised crimes, which require an internationally co-ordinated response, both at the multilateral and regional level.