Assessing impact/outcome has become an important topic for libraries since several years, as in times of electronic information the benefit of libraries is no longer seen as self-evident. In addition, there is a rising demand for accountability, for showing evidence of the benefits achieved with the given resources.
Various projects worldwide are trying to prove that use of library services can positively influence skills and competences, attitudes and behaviour of users. The benefits that users experience by using library services can be assessed in terms of knowledge gained, higher information literacy, higher academic or professional success, social inclusion, and increase in individual well-being.
Methods have been developed for making such influences visible and quantifiable, using the existing experience in the sector of non-profit organizations. The instruments that have been proposed and tested cover "soft" methods like surveys, interviews, focus groups, or observation and also tests, analysis of publications, or the comparison of use data to data of academic or professional success. The main problem is of course, that influences on an individual are manifold and that therefore it is difficult to trace changes and improvements back to the library.
The presentation discusses the possible impacts of library services, the methods of assessing such impacts, and the problems of impact analysis.