In 2002 Sweet & Maxwell began a long term project to apply a controlled vocabulary to their products, both in print and online. This vocabulary is essentially a thesaurus, structured on the principles of facet analysis, called the Legal Taxonomy. Sweet & Maxwell produce a wide range of legal publications that attempt to cover the gamut of a lawyer’s information sources. As everybody working in legal information knows, very few of a lawyer’s information needs will be met by reference to just one source. A typical query may start with reference to a textbook, followed by a check on recent case law or legislation, and finally the enquirer may have recourse to up-to-date commentary in a journal. Indexing all of these sources using a controlled vocabulary allows a single query to be formulated, thereby reducing the work that has to be done by the researcher. At its simplest, if Contract of employment is the term always used to describe that concept in all the publications the researcher looks at, then no time need be wasted in seeking alternative descriptions such as Employment contract. Although the advantages to be gained from this approach become more obscure when viewing individual sources in isolation, particularly traditional paper sources, the greatest benefits arise when the entire collection has been indexed consistently. All of the content indexed in accordance with the controlled vocabulary becomes accessible by means of each and every concept described in the vocabulary.