This chapter discusses disaster management open source software tools, such as Hazus-MH by Federal Emergency Management Authority and the Sahana Disaster Management Tool. Two important tools are usually implemented worldwide in disaster engineering. One is the Hazus Loss Estimation Tool used by the Federal Emergency Management Authority in the United States, and the second is the Sahana Disaster Management Tool. Due to the courtesy of the Sahana Foundation Edinburg, the author was provided access to the computer-based Sahana Disaster Management Tool. Government planners, GIS specialists and emergency managers use Hazus to determine losses and the most beneficial mitigation approaches to take to minimize them. Hazus can be used in assessment steps in the mitigation planning process which is the foundation for a community's long-term strategy to reduce disaster losses and break the cycle of the disaster damage, reconstruction and repeated damage.