Evaluating and guaranteeing customer satisfaction in the long-term is an integral part of quality management in libraries. Quality is defined as “all of the characteristics and features of a product or a service, which relate to their suitability for fulfilling fixed or given requirements” [EOQ 1976] and it is determined by the subjective evaluation of the customer. Surveys are used to gather individual opinions and to compress them into an overall evaluation, which then serves as the basis for an analysis of strengths and weaknesses. This article is based on the analysis of a best practice report conducted by the Central Library of Forschungszentrum Jülich. An online survey performed in 2007 was used to assess the satisfaction and expectations of library users and the results were incorporated into an improvement list. “User satisfaction” is particularly important in a special library. There is no such thing as an homogenous user. Instead, a wide variety of user groups exist and the library must adequately react to their individual needs. For the Central Library of Forschungszentrum Jülich, customer orientation means continuously assessing customer satisfaction, further developing the range of information services available in order to meet high quality demands, and optimising products and services with the involvement of the customer.