Horn of Africa has been gravely affected by the proliferation of small arms and light weapons. Causes to the proliferation of small arms and light weapons are raised from the strategic importance of the sub region, existence of insurgent movements and civil wars, frequent cattle rustling, and interstate conflict. These causes basically have invited the proliferation of small arms and light weapons in the Horn of Africa. The sub region is engulfed by illicit small arms and light weapons from different sources. The major sources are impact of colonialism, effect of the Cold War, impact of demobilization, state failure in Somalia, and covert arms transfer to neighboring countries. In actual terms, SALW's spread from pastoral areas to urban areas with limited disarmament effort. Like wise other Horn of Africa countries, Ethiopia has also shares the problem, cause, and source of SALWs. These days people have learned to establish cooperation against SALWs at global, continental and sub regional level. The United Nations Plan of Action, the Bamako Declaration of the OAU, and the Nairobi Protocol to the Great lakes and the Horn of Africa is the result of good effort and commitment.