This paper describes a method which was used to evaluate the cost-effectiveness of three different ways of supplying periodical articles in an academic library. The methods considered were: subscribing to a periodical title (ownership); individual article supply provided by two electronic document delivery services, ArticlesFirst of OCLC FirstSearch and UnCover; and traditional article supply through the British Library Document Supply Centre. The operational costs of the alternatives are obtained by taking a management accounting approach and are examined in relation to the provision of the services within the library of St. Patrick's College, Maynooth, Ireland. The cost-per-use of owning a periodical title is calculated based on the operational costs of the Periodicals Department of the library, its subscription price and a lifetime use determined by examination of the current requests for articles made through the library's Inter-Library Loans Department. The cost-per-use for the other services are also calculated based on their operational costs and document delivery charges.