Each year thousands of people die in natural and man-made disasters because organizations in charge of mitigating the disasters are unable to effectively handle them. Building effective disaster management organizations is a complicated and challenging undertaking. A good understanding of the multiple dimensions of disaster response and mitigation and their interrelationships is needed to build effective systems. This is particularly true in the case of the Caribbean region’s Caribbean Disaster and Emergency Response Agency (CDERA). CDERA is a network organization of the disaster management organizations multiple independent developing island nations with economies that are not diverse and a geography that predisposes them to natural hazards. This dissertation presents the results of an empirical research on the effects of organizational form, organizational capacity, and organizational learning on the effectiveness of CDERA in its responses to disasters. The case study methodology was used to collect and interpret the information about CDERA’s response and the factors affecting its effectiveness in two recent natural disasters: Hurricanes Ivan and Dean. The data were collected from twenty six interviews and archival information to answer the questions about organizational form, organizational capacity, and organizational learning. The model applied in this research project was developed on the basis of the general literature on disaster management and the literature on the US Federal Emergency Management Agency. This holistic approach utilized in this dissertation, is an important contribution to the literature on disaster management. This conceptualization differs from other approaches used to examine disaster management agencies and their deficiencies. Other approaches have examined the input variables in isolation and that resulted in a thwarted view of the organizational complexities of disaster management systems thereby limiting our understanding of how to fix the problems encountered in such systems. The dissertation adds to the knowledge base on how to build organizational effectiveness. The analyses of interviews and archival information show that the complexities usually faced by disaster management organizations are further compounded in the CDERA environment. It is known that disaster response and mitigation require complex organizations. Hybrids of network and bureaucratic forms are necessary to properly plan for and respond to disasters. In addition, The CDERA case shows that the positions of its national affiliates in government bureaucracies are very important for them to have proper access to resources. It is known that organizational capacity is an important prerequisite for effectiveness in disaster management entities. The findings of this study show that some specific capacity variables, such as technology, human resources, and technical expertise, are more important than others. The findings indicate that a set of organizational capacity variables that were not anticipated in the original model of this dissertation are also important. These variables are managing for results, integration and alignment of mission, vision and practice, transportation management, and business continuity (including succession management). Organizational learning constitutes an important feedback loop. It helps to regulate the system by highlighting the gaps in capacity in particular. The findings of the case study reaffirms that disaster management systems operate in complex environments, that the events these systems handle are unpredictable and complex, and that the systems must be equipped with proper …