What do we really know about the quality of teaching in Poland? For years, we’ve relied on intuition, tradition, and anecdote. But now, for the first time, we have something different: hard data about what teachers actually know about teaching itself — their general pedagogical knowledge, or GPK. The OECD’s Teacher Knowledge Survey gives us a new lens. And through that lens, Poland’s teachers emerge as highly competent, deeply committed, and internationally competitive. But there are threats.