The premise that using language is a thinking process is central to the computerized diagnostic test being developed by Educational Testing Service (ETS). The test developers are making a significant educational contribution by describing the reciprocal and dynamic relationship between language and thinking. Reading comprehension has been characterized by two general cognitive processes: understanding the structure of a text, and using metacognitive strategies to facilitate understanding of the text. Other cognitive skills involved in reading are concept formation, relating concepts to each other and to a larger framework, problem solving, and critical reflection. Writing also requires skillful use of these same cognitive activities. Successful readers and successful writers are effective precisely because they have developed the thinking abilities which underlie the processes of reading and writing. A project conducted at La Guardia Community College supports the usefulness of ETS's test, which identifies thinking abilities of the reading and writing processes. Courses in reading, writing, and speech have been taught and linked to a critical thinking course. Faculty reaction to this approach has been positive. The results suggest that approaching language as a thinking process is appropriate and effective. (GDC)