The purpose of this study is to provide a comprehensive account on case-based instructional practices. Semester-long participant observation records in torts, marketing, and online instructional design classes, instructor interviews, course syllabi and teaching materials were used to describe the within-class complexity of the practices in terms of the program, the instructor, the class, and the case activity. Across-class analyses resulted in identifying patterns of similarities and differences alongside the dimensions of instructor, cases, case-based course design, and case discussion facilitation. In particular, the following four empirical assertions were constructed: (a) The instructors had positive beliefs about case-based learning and articulated course learning goals that aligned with the known assumptions of case-based learning, but different assumptions about learner prior knowledge and skills. (b) The instructors used cases that afforded learning of professional decision making and argumentation, but portrayed the nuanced disciplinary differences in professional thinking and represented the professional world in a disciplinary manner. (c) The instructors used different case-based course design strategies to communicate goals, assign cases, provide supports, promote participation, and assess course learning in each class. (b) The instructors enacted different case discussion facilitation strategies to prepare learners, structure, trigger, guide discussions, encourage participation, and ensure case-based learning in each class. The study concludes with a discussion on why practices were different across the disciplinary classes. This study informs research on case-based instruction by suggesting an empirical framework for case-based instructional practice. It also illuminates how a single instructional approach can be interpreted and applied differently across disciplines. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]