Most people are familiar with the practice of medical rounds, in which interns and mentoring physicians visit patients in an institutional setting, observe their various conditions, discuss what they observed, and analyze possible treatment options and outcomes. In the medical profession, making these rounds is viewed as a significant and highly important form of professional learning. While medical rounds for physicians and instructional rounds for teachers--called Teacher Rounds to distinguish it from the practice of rounds by administrators--are not precisely the same, the comparison is a shortcut way to begin thinking about what constitutes this kind of school-based professional learning. Teacher Rounds is a strategy many schools use as part of a comprehensive program for improving teaching and learning. Teacher Rounds is based on these core assumptions about what it takes to create a culture of professional growth and learning: (1) Teaching practice is best when it is public and collaborative; (2) Teaching is strongest when teachers collect data and act on it rather than rely on intuitive judgments; (3) Teachers who are self-reflective about their teaching are more effective teachers; (4) Significant improvements in teaching practice occur slowly, in small steps; and (5) Development of teacher leadership improves instruction. The practice of Teacher Rounds is professional learning that embodies all of these assumptions. This article describes the reasons why Teacher Rounds is so effective, how Teacher Rounds aligns with the Standards of Professional Learning and opens the door to the the Common Core State Standards, and provides detailed steps on how to implement the Teacher Rounds process.