In contrast to classroom assessments that can provide immediate feedback in the context of ongoing instruction, large-scale assessments are necessarily broader survey instruments, administered once-per-year and standardized to ensure comparability across contexts. Classroom and large-scale assessments must each be tailored in design to serve their respective purposes, but they can be symbiotic if they share a common model of what it means to do good work in a discipline and how that expertise develops over time. Three purposes of large-scale assessment programs are addressed—exemplification of learning goals, program “diagnosis,” and certification or “screening” of individual student achievement. Particular attention is given to the ways that assessments should be redesigned to heighten their contribution to student learning. In addition, large-scale assessments are considered as both the site and impetus for professional development.