The CSDP Handbook on Advisory Support to Tackling Organised Crime (2019) was prepared by RIOC Paulius Klikunas and Tanja Tamminen in close cooperation with Sergii Rybchenko and Ievgen Vorobiov. All four served in the EU Advisory Mission (EUAM) in Ukraine. The authors were motivated to write this book as they knew what type of everyday challenges Common Security and Defence Policy (CSDP) mission members encounter. The authors designed the handbook to assist advisers supporting host-country authorities to develop strategies, structures and tools to better tackle organised crime and disrupt organised crime groups.