Arguing that writers must be able to evaluate the quality and effectiveness of the texts they produce, this paper begins by isolating some of the persistent questions raised by people in education, business, and government who want to judge how well their texts are working. The paper then compares the cognitive processes involved in "reading to comprehend text" with those involved in "reading to evaluate and revise text," stressing that even experienced writers often need help in detecting and diagnosing text problems. The paper then characterizes three general classes of tests for evaluating text quality: (1) text-focused; (2) expert-judgment-focused; and (3) reader-focused approaches. The paper reviews typical methods within each class and discusses the relative advantages of reader-focused methods over other approaches. (Four figures are included; 150 references are attached.) (RS)