Assessment for learning, as opposed to assessment of learning, requires educators to make a major shift--from quality control in learning to quality assurance, from assessing at the end of teaching to assessing while learning is still taking place. Five nonnegotiable strategies define the territory of assessment for learning: clarifying and sharing learning intentions and criteria for success; engineering effective classroom discussions, questions, and learning tasks; providing feedback that moves learners forward; activating students as owners of their own learning; and activating students as instructional resources for one another.