Electronic information integration has the potential to rationalise and improve business processes in many public and private sectors. A key challenge in any information integration task is to resolve the heterogeneity among the semantic terminologies used in the various information sources to be integrated. This paper describes how ontologies can be developed to achieve this resolution of semantic heterogeneity. We discuss a case study with a particular focus in the application domain of health care, namely palliative care. We begin by describing the methodology upon which our ontology is designed. The methodology description includes details on the conceptual framework and formalization of the framework to design our ontology. We then illustrate proposed implementation of the ontology in two ways. First, we show its use in creating patient specific clinical practice guidelines. Second, we describe the use of the ontology in pilliative care systems by showing how it can assist in database design, decision support, and act as knowledge management tool for facilitating information sharing.