Carolan and Guinn assert that differentiated instruction helps diversity thrive. Observing how experienced teachers practice differentiation in real-life situations helps teachers who are reluctant to try such strategies take the plunge. The authors draw on two observational studies they conducted of five expert teachers in a high-performing, heterogeneous district. They identify four characteristics common to teachers who are master differentiators: offering personalized scaffolding, using flexible means to reach defined ends, mining subject-area expertise, and creating a caring classroom where differences are seen as assets. The authors describe examples of each characteristic in action.