This CALDER research brief builds on pioneering research by the Measures of Effective Teaching Project (Kane et al., 2013) and Jackson (2018) to look at two measures of teacher quality-value-added measures (VAMs) for both test outcomes and non-test outcomes--and what they can tell education leaders about the teacher workforce. Both measures use a value-added framework to separate out a teacher's contributions to student outcomes from other factors, like a student's previous academic record or economic circumstances. By trying to isolate teacher contributions to student outcomes, the measures speak to the question, "would students be better off with a different teacher?"