The study aims to explore in-service teachers' epistemological beliefs about the following five critical paradigms in second language education and their corresponding practices: (1) inductive/deductive grammar instruction, (2) intensive/extensive reading, (3) looking up unknown words in the dictionary/guessing from context, (4) focusing on accuracy/proficiency, and (5) task-based/test-based learning. The findings reveal that even though in-service teachers possess certain epistemological beliefs that shape the nature of their pedagogical practice, there is an ongoing negotiation between the dominant (e.g., students' test performance) and less-dominant factors involved in their decision making. The teaching practice is both an individual and socially constructed behavior.