This article describes professional development activities in specific suburban school districts that are experiencing rapid growth in their proportions of students of color, culturally and linguistically diverse students, and students from low-income families. As the author has worked with these districts, he has identified five phases of professional development that help transform school staffs to meet the challenge of changing demographics: (1) building trust; (2) engaging personal culture; (3) confronting issues of social dominance and social justice; (4) transforming instructional practices; and (5) engaging the entire school community.