We argue that manual and automatic thesauruses are alternative resources for the same NLP tasks. This involves the radical step of interpreting manual thesauruses as classifications of words rather than word senses: the case for this is made. The range of roles for thesauruses within NLP is briefly presented and the WASPS thesaurus is introduced. Thesaurus evaluation is now becoming urgent. A range of evaluation strategies, all embedded within NLP tasks, is proposed.