Q: What was the impetus for focusing on the principal pipeline? Nicholas Pelzer: Around 2000, when The Wallace Foundation started focusing on leadership, it wasn’t really on the national agenda. It was considered a tertiary issue.Through the first 10 years of our work on the topic, we were asking questions like, “Does leadership matter, and if so, in what way?” and “How do you develop effective school leaders?” We started seeing an emerging body of evidence that leadership matters. For example, Kenneth Leithwood and his colleagues found that principals’ influence on student achievement is second only to that of classroom instruction. We learned a lot about what elements contributed to developing effective school leaders, but we didn’t have proof of concept that effective leadership could