Floods are among the most hazardous and destructive natural disasters with the potential to wreak havoc on humans, material assets, cultural wealth and ecological resources. Several countries have used different flood management and control measures both structural (e.g. constructing levees, dams, storm surge barriers) and non structural (e.g. applying spatial measures, developing flood forecasting and early warning systems) to reduce their vulnerability and exposure to floods. These flood management and control measures can be addressed using the safety chain concept. Originally, the safety chain concept consisted of four links: mitigation, preparation, response and recovery. Now, the safety chain concept is well adopted in different countries with slight adjustments. Multiple stakeholders and actors are involved in the various links of the safety chain. In many countries, these actors include the government (e.g. national, provincial and local), emergency services (police, fire brigades, medical aid) and the water authorities. However, many more actors are also involved. Due to the involvement of many actors in different activities, it is difficult to compare the construction and operation of Flood Control Domain in different countries. In line with the above problem, the objective of this thesis project is to develop an enterprise ontology that will show how the Flood Control Domain is constructed and operated by identifying the essential operations performed in the domain, highlighting the interrelationships between these operations and information objects that are relevant for the operations in the domain, and illustrating its use in the Netherlands and the United States. The literature research resulted in a concise overview of ontology and enterprise ontology. There are various definitions of ontology. In this thesis project, the chosen definition of ontology is: a formal, specification of shared conceptualization. The notion of ontology as applied in this document is the notion of system ontology whose main purpose is to understand the essence of construction and operations of complete systems; more specifically of enterprises. Enterprise ontology can be described as a conceptual model of an enterprise that is coherent, comprehensive, consistent and concise, and that only shows the essence of the operation of an enterprise model, independent from implementation and realization. The Design and Engineering Methodology for Organizations (DEMO) methodology was selected to develop the enterprise ontology for the Flood Control Domain. DEMO provides a step-by-step procedure that helps to derive the ontology of an enterprise in a systematic way. Following DEMO methodology, the starting point for developing enterprise ontology is the collection of all available documentation about the enterprise. Therefore, a thorough analysis of the Flood Control Domain was conducted through literature reviews, interviews and a case study. Based on the analysis of the Flood Control Domain, an Explanatory Case describing the domain was provided using the safety chain approach, which is described in five links: the pro-action, prevention, preparation, response and recovery. Based on the Explanatory Case, the Perfoma Analysis was conducted to capture the performa human abilities that concern the essential productions in an organization. On the basis of the Perfoma Analysis, the transactions, which represent the essential operations in the Flood Control Domain, were identified. These transactions and their specifications were presented in a Transaction Result Table (TRT). Next, the Construction Model of the Flood Control Domain was developed. The Construction Model shows the identified transactions, the initiator(s) and an executor for each of the identified transactions as well as the information links between the actor roles and the information banks. In the next step of this research, the interrelationships between the identified essential operations in the Flood Control Domain were shown. Here, the Process Model of the Flood Control Domain was constructed. In the Process Model, the logical sequence of steps for which a transaction is performed is provided; hence, the interrelationship between the transactions. The Process Model also enables every transaction pattern in the Construction Model to be seen, as well as the specific transaction pattern of the transaction type. Then, the information objects necessary for the organizations in the Flood Control Domain were presented using the State Model, which can be used as a data dictionary of an organization showing the object classes, the fact types, the result types and the existential laws. In the next phase of the research, the focus was to show how the developed enterprise ontology is used in the Netherlands and the United States. Here, the concern was to show the organizations in the two countries responsible for performing the identified transaction, also regarded as the essential operations, in the Flood Control Domain. In order to do this, the Construction Model was re-drawn whereby the abstract actor roles were replaced with the existing organizations in the Netherlands and the United States. In the final phase of this research, the thesis results were analyzed. In general, the developed enterprise ontology for the Flood Control Domain seems to be generic since most of the actors who acted as initiators and executor of certain transactions could be mapped to the existing organizations in the Netherlands and the United States. However, some differences were evident in the implementation of flood control operations in the Netherlands and the United States. Such differences could be seen in flood management activities. For instance, while a hierarchical relationship exists between the US Army Corps of Engineers and the local sponsors, such as the levee districts, a horizontal relationship can be seen between Rijkswaterstaat and the water boards in the Netherlands. Moreover, the analysis shows that due to the size of the two countries, the local governments in the United States have more roles and responsibilities as compared to the local governments in the Netherlands. The analysis highlights the differences between the two countries on the use of flood insurance policy. While the flood insurance policy is commonly used and highly emphasized in the United States in order to reduce flood losses, such a policy is not applicable in the Netherlands. The recommendations for future work include a mapping of the identified transactions to the applications or existing information systems both in the Netherlands and the United States, development of a high level Construction Model of the Flood Control Domain and the initiation of an Action Model. The thesis results should be shared with a large group of people and an ideal enterprise ontology should be developed for the Flood Control Domain that different countries can use to compare themselves with one another.