This article reports the findings from a year-long study of 6 writing teachers in an urban elementary school who also received intensive professional development in writing instruction from a nonprofit organization. Repeated observations demonstrated that the teachers displayed consistency in their use of the core instructional elements associated with writing workshop, which aligned with the emphasis of the professional development support. However, the teachers exhibited substantial variability in their use of student engagement tactics, management techniques, and instructional supports. According to survey data, the teachers demonstrated a strong and relatively stable sense of teaching efficacy and held a fairly balanced view of the importance of explicit and incidental writing instruction, and these beliefs were related to their instructional practices. Interviews with the teachers highlighted the relevance of teachers' own writing behaviors and attitudes. (Contains 1 figure, 6 tables, and 2 notes.)