The cultural industries are one of the biggest employers in the world. In addition to museums and galleries, there are many governmental and non-governmental agencies that work to conserve, research and promote cultural heritage and to further the production of art. Furthermore, History of Art graduates will be especially competitive for posts in any area that requires combinations of visual and verbal skills, such as publishing, advertising, marketing and web-based media, as well as entering the wide range of professions available to all humanities graduates.
The University's Careers Service is a dedicated service that can provide more help and information. Please see their website: http://www.careers.ox.ac.uk/