This chapter delves into the impact of case studies within applied linguistics and language education, underscoring its indispensable role in navigating the complexities of contemporary language learning and teaching. The chapter illuminates how this approach facilitates a nuanced understanding of linguistic phenomena within real-life contexts by examining the case study method's core principles, design, and implementation strategies. Emphasizing the flexibility and adaptability of case studies, the chapter showcases their capacity to offer in-depth, rich insights that transcend traditional research methodologies. This chapter also articulates an argument for integrating case studies in advancing the field's knowledge base and practice by aligning its mission with the book's overarching aim. Concluding with a reflective synthesis, the chapter invites researchers and practitioners alike to engage with the case study, highlighting its transformative potential and enduring impact on applied linguistics and language education.