It is argued that tests of English as a Second Language based on specific instructional materials, reflecting both real-world and classroom language activities, can satisfy measurement needs and provide interesting psycholinguistic insights. It is also proposed that the potential for mismatch between test and materials can be overcome by several strategies, including: integrating testing programs into institutional life, rather than treating testing as ancillary to learning; using test content that reflects classroom activities and student lives; and active encouragement of teachers' involvement in test writing, including appropriate training. (MSE)