1. A method of automatically searching through a store of electronic documents, the method comprising: controlling a user interface to permit a user to enter a search term; carrying out a search using the search term; categorizing the documents returned by the search into a plurality of distinct categories; and controlling the user interface to present the documents returned by the search, or references thereto, in a grouped manner such that documents of a particular category are grouped together, wherein the categories are selected in dependence upon the search term, wherein the categories are selected by identifying concepts within a personalized ontology which match words from the search term to use as the categories, and wherein the personalized ontology is formed by setting constraints on the allowable values of attributes of concepts within a common ontology.