Outcomes of guidance can be assessed at these three levels: individual, where they are immediate; organizational, where they are intermediate; or societal, where they are ultimate. They may result in learning outcomes, school effectiveness, economic benefits, or social benefits. Various designs of outcome evaluation are described and recommendations are made as to which design is appropriate based upon the objectives of policy and the type of evidence available. A review of literature finds that convincing evidence of positive outcomes of career guidance has been difficult to quantify. Future research must be more longitudinal in order to identify long-term, deep-seated effects and that the three key players in the establishment of criteria for measurement of outcomes policy makers, practitioners, and researchers must engage in dialogue and agree on common approaches. (As part of a study of guidance systems in European Union member states, this paper considers different approaches to measurement of outcomes from career information and guidance service delivery, provides exemplars of different approaches, summarizes reviews of evidence using these approaches, and outlines policy priorities for the collection of evidence in the future and for effective sharing and dissemination of such evidence. It includes 86 references and 1 chart.) (MO)