This report presents the results of a survey of Digital Library Federation members that examined the kinds of assessments they were conducting, what they did with the results, and what worked well or not so well. The first section of the report is an introduction that describes the report structure and summarizes challenges in assessment. The second section presents results related to user studies, including surveys (questionnaires), focus groups, user protocols, and other effective research methods. The third section addresses the following questions related to usage studies of electronic resources: (1) What is transaction log analysis? (2) Why do libraries conduct transaction log analysis? (3) How do libraries conduct transaction log analysis? (4) Who uses the results of transaction log analysis? and (5) What are the issues, problems, and challenges with transaction log analysis? The fourth section covers general issues and challenges in planning and implementing a research project. The fifth section presents conclusions and considers future directions. Appendices include: references and a selected bibliography; a list of participating institutions; the survey questions; and traditional input, output, and outcome measures. (MES)