This paper reflects on the growing importance of usage statistics, citing increased provision of electronic journals, their increasing use, and in particular their increasing cost. The need selectively to promote particular services and titles, and the place of performance indicators, are also covered. Particular examples of the value of usage statistics are given in relation to budget allocation, collection management and collection development, and marketing of journal availability to users. The importance of statistics that are comprehensive, comparable, and easy to analyse is stressed, and current efforts to increase standardisation are supported. This paper is adapted from a presentation prepared for a one-day seminar on Usage Data and E-journals, organised by the UK Serials Group in October 2001.