The issue of illicit arms trade has been present for many years as a global phenomenon. It is considered a manifestation of organized crime and an area of concern dealt with by many institutions in different countries in the world. Firearms account for large number of casualties through history, but also nowadays, and due to their lethal potential, they are subject of severe restrictions. Particularly problematic is the illicit trade in small arms and light weapons, as manufacture of these type of weapons cannot be restricted due to the need for mentioned products coming from military and law enforcement officials. The scope and modality of illicit trafficking varies among different countries, while concealment of its process and lack of information, largely facilitates these kinds of transfers, especially in less developed countries, where products find their way unnoticed by respective authorities. This paper will cover key characteristics of illicit arms trade as a phenomenon in the contemporary world. In addition, it will seek to describe how, what for and in which moment do legal weapons become part of illegal domain. Furthermore, the most frequent flows to their end users will be described, as well as features of actors involved in this type of trade. The paper will provide statistical overview in terms of key indicators, discuss what has been done on international level in context of criminal justice response and efforts focused on preventing and countering illicit arms trade and review existing strategies and interventions regarding their impact, aiming to create effective approach in fighting against this form of crime.