The war in Ukraine, which began in 2014 and escalated in 2022, has showcased contemporary warfare strategies that have been observed and adopted by non-state armed groups (NSAGs), including insurgents, paramilitaries, and mercenaries. The relationship between terrorism, organised crime, and non-state armed actors (NSAAs) has been analysed as a strategic means of exploiting illicit markets. This relationship is primarily evident in failed and fragile states, where it is used to profit from war, technology, and the cyber environment. This chapter analyses the impact of NSAAs on the global security agenda, particularly in light of technological advances. It argues that this impact has significantly changed since the war in Ukraine, representing a new threat capable of challenging security dynamics at regional and global levels.