Consistent, excellent teaching is the single greatest factor in improving student achievement over time. School leadership is the second. Excellent teaching and strong leadership require deliberate, ongoing professional learning. In working with high-poverty school systems over time, the following basics emerge: (1) time; (2) content; (3) appropriate processes; and (4) supportive contexts. While the basics of professional development are essential to achieve social justice, their existence does not ensure that justice will be served. Schools that intentionally pursue social justice hold basic tenets that frame how to design, understand, implement, and measure professional learning. They are: (1) Design professional learning that focuses on students who have been traditionally underserved and marginalized; (2) Use solid data to understand students as people and as learners; and (3) Measure impact based on the underserved, and keep at it. While policies may help or deter the effort, it is up to local educators to pursue social justice with fidelity.