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. 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," 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." 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. Additionally, nearly 90% of Association of American Universities (AAU) member institutions reported using quantitative data to collect information on student learning outcomes, with 70% reporting that they had one employee or office specifically charged with developing, coordinating, or implementing assessments of student learning. Amid the increasing calls for accountability to demonstrate students' learning, colleges and universities are currently confronting competing demands for fewer resources; 5 consequently, it is even more vital that programs and services demonstrate their contributions to student outcomes. Academic libraries are no exception and, over the last decade, researchers have expanded their efforts to better understand how libraries contribute to students' success, including students' retention 6 and academic achievement. 7 One critical area of students' learning and development often explored by library 11 attest to the connections between libraries and student learning. As a result, the library community is much more likely to create student learning outcomes and use a variety of forma...