School principals are essential for ensuring that students have access to strong educational opportunities. They shape a vision of academic success for all students; create a climate hospitable to education; cultivate leadership in others so that teachers and other adults feel empowered to realize their schools' visions; guide instructional decisions that improve teaching and learning; and manage people, data, and processes to foster school improvement. Research has found that high-quality professional learning opportunities for principals--including preparation programs, induction supports for early-career principals, ongoing training, one-on-one support through coaching and mentoring, and peer networks--can build leadership capacity. To learn more about principals' opportunities for professional learning, the National Association of Elementary School Principals (NAESP) and the Learning Policy Institute (LPI) collaborated on a national principal study. The authors analyzed survey data that addressed professional learning experiences for all principals using descriptive statistics, and the authors examined differences among groups of principals with different experience levels and those working in schools with distinctive characteristics. The study found that: (1) Most elementary school principals had access to professional development content identified as important for building leadership capacity, including topics in leading equitable schools; (2) Many elementary school principals appear not to have had the opportunity to participate in authentic, job-embedded professional learning; (3) More than half of all elementary school principals wanted more professional development across all topics, but principals were most likely to want additional professional development that focuses on whole child education; (4) More than four in five elementary school principals (84%) indicated that they faced obstacles to pursuing professional development; and (5) Most elementary school principals reported that their districts can play a role in helping to overcome obstacles to professional learning and can support principals' continuous improvement, but this varied by the proportion of students in poverty and students of color in schools. [For the research brief, see ED610879.]