This paper presents a brief overview of the status of K-12 accountability testing in the United States. Following that review, we describe an assessment-system model designed to overcome the problems associated with current approaches to accountability testing. In particular, we propose a model in which accountability assessment, formative assessment, and professional support are built on the same conceptual base and work synergistically with one another. We close with a brief discussion of the role of technology and a review of the challenges that must be met if the highly ambitious system we suggest is to be realized.