This paper discusses the extent of eruption of Merapi volcano in 1994. It looks at the effects associated with the volcano as it erupted. The damages were inflicted on both the abiotic and biotic environments. The eruption occurred in the southern parts of the volcano. Because of the potential problems the volcano has, this has called for government involvement as an attempt to minimise the casualties. This has been done by intergovernmental cooperation for instance through the establishment of disaster prevention projects like Sobo Technical Centre, Merapi Volcano Project and the office purposely concerned with the investigation on the activities of Merapi. These projects cooperate to establish the hazard maps.