Since the fall of the Iron Curtain and the subsequent evaporation of the Communist threat, at the beginning of 1990s, scholars have shifted their attention to the threatening role of non-state criminal actors. The inter-linkages between organised crime, terrorism, corruption and politics have been depicted by the post Cold War security discourse as significant obstacles to democratic processes, security and stability at the national regional and global levels. Motivated by theoretical considerations, this article provides an overview of the conceptual underpinnings of existing research on the crime-terror nexus and attempts to synthesise existing theories.