Evaluating serials vendors is a way to ensure cost-effective quality service. The ""Guide to Performance Evaluation of Serials Vendors"" provides the information necessary to collect and analyze data on serial vendor performance, compare vendor performance and systems, and incorporate vendor evaluation into regular work activity so that crisis situations do not force the issue. Among the topics covered are: applying quantitative and qualitative measures; techniques for evaluating subscription agents and standing order vendors; obtaining data for bid situations; and disclosure of evaluation results. An annotated bibliography leads to more information on evaluating serials vendors. The ""Guide to Performance Evaluation of Serials Vendors"" provides an approach to ensuring continual high quality and consistent service and access for library customers.