Academic and research libraries have been increasing their efforts for a number of years to demonstrate their contributions to student learning outcomes in support of the institutional educational mission. Whether through one-shot instruction or credited classes, libraries invest a great deal of time and effort in instructional programs. A key challenge is the development of assessment methods that provide data useful for understanding the impact of these offerings. Following an Editor's Note by M. Sue Baughman, this issue of "Research Library Issues" includes two case studies that explore various data sources to assess student learning outcomes and experiences. In the first article, "The Impact of Academic Library Resources on First-Year Students' Learning Outcomes," (Krista M. Soria, Kate Peterson, Jan Fransen, and Shane Nackerud) a team from the University of Minnesota presents the findings of their recent study. By examining student-reported feedback about use of library resources (checking out books, using electronic resources, engaging in reference services, etc.) and about high-level learning outcomes (critical thinking and analytical skills, writing skills, and reading comprehension), the team argues that the use of library resources does play a role in students' development of learning outcomes. Cornell University Library staff describe their exploration of a variety of data sources to assess students' experiences, not just their skills, in the second article, "Multi-Method Assessment to Improve Library Instruction" (Zsuzsa Koltay and Kornelia Tancheva). This study examined faculty perceptions of students' information literacy skills and use of library instruction as well as students' opinions about the usefulness of library instructional offerings. Coupling these survey results with information gleaned from student focus groups, the library decided to conduct a pilot project with Cornell's College of Engineering. The well-received pilot project produced short, instructional videos to help students develop specific library skills on an as-needed basis. Both teams approached their projects with somewhat similar goals--to better understand the impact of the library on student learning outcomes and experiences. They used different methodologies in examining their research questions and they share interesting results. Both teams also provide helpful conclusions and next steps.