Ontologies provide a shared and common understanding of a domain that can be communicated between people and across application systems. An ontology for a certain domain can be created from scratch or by merging existing ontologies in the same domain. Establishing ontology from scratch is hard and expensive. Multiple ontologies of different systems for the same domain may be dissimilar, thus, various parties with different ontologies do not fully understand each other in spite of these ontologies are for the same domain. To solve this problem, it is necessary to integrate these ontologies. Integrated ontology, should be consistent and has no redundancy. This paper presents a semi-automated system for building an integrated ontology by matching and merging existing ontologies.