Ontologists generally work in the field of knowledge representation and management. They develop and maintain ontologies, which are formal representations of knowledge that capture the concepts and relationships within a particular domain. Ontologists work with subject matter experts to identify and define the concepts and relationships that are important within a domain, and then use formal languages and tools to create and maintain the ontology. They may also work on developing applications that use ontologies to support knowledge management, information retrieval, and other tasks. Ontologists may work in a variety of industries, including healthcare, finance, and technology.