Online assessment, in its infancy, is likely to facilitate a variety of innovations in both formative and summative assessment. This chapter focuses on the potential of online assessment to accelerate learning via effective links to instruction. A case is made that detailed learning maps of academic progress are especially conducive to effective skill and concept diagnosis and prescriptive learning, contributing construct validity and precision to assessment results and coherence to instructional interventions. Item adaptive testing using learning maps and the paradigm of intelligent agents is discussed in the context of a vision of a seamless integration of assessment and instruction. The chapter is primarily speculative rather than technical.