Research shows how schools can create more powerful professional development experiences. To help young people learn the more complex and analytical skills they need for the 21st century, teachers must learn to teach in ways that develop higher-order thinking and performance. To develop the sophisticated teaching required for this mission, education systems must offer more effective professional learning than has traditionally been available. What does research say about the kind of professional learning opportunities that improve instruction and student achievement? High-Quality Professional Development: A New Definition In the last two decades, research has defined a new paradigm for professional development—one that rejects the ineffective "drive-by" workshop model of the past in favor of more powerful opportunities (Stein, Smith, & Silver, 1999). Research has begun to create a consensus about the content, context, and design of high-quality professional development (Hawley & Valli, 1999). Content: Centered on Student Learning The content of professional development can make the difference between enhancing teachers' competence and simply providing a forum for teachers to talk. The most useful professional development emphasizes active teaching, assessment, observation, and reflection rather than abstract discussions (Darling-Hammond & McLaughlin, 1995). Professional development that focuses on student learning and helps teachers develop the pedagogical skills to teach specific kinds of content has strong positive effects on practice (Blank, de las Alas, & Smith, 2007; Wenglinsky, 2000). Research Review/Teacher Learning: What Matters?. Available from: https://www.researchgate.net/publication/228625772_Research_ReviewTeacher_Learning_What_Matters [accessed Jun 27, 2017].