3 Hoeber, Orland 2007 Proceedings of the IEEE/WIC/ACM International Conference on Web Intelligence IEEE Computer Society 650-654 0-7695-3026-5 In general, Web search engines perform well for users whose information needs are well-defined. When searchers can provide specific terms that adequately describe the information they are seeking, the top search results are commonly very relevant. However, when users wish to explore a topic, little assistance is provided by Web search engines to help users in finding the information they seek. In this paper, a system that supports exploratory search through the visual specification of utility functions is presented. Users are able to recognize potentially relevant terms using a term frequency histogram, and can indicate their preferences for these in a visual manner. The search results are re-sorted based on the corresponding utility function; colour coding allows users to easily locate the selected terms within the search results list.