The effectiveness of the Test of Standard Written English (TSWE) as an aid in placing students into introductory English courses was studied by relating test scores to course outcomes for students entering the University of Houston between the fall of 1977 and the spring of 1981. For students placed into the regular introductory English composition course, TSWE scores were effective in predicting end-of-course grades, end-of-course essay scores, and endof- course test scores. Students with scores below 40 on the TSWE were estimated to have less than 58 chances in 100 of obtaining grades of C or higher in the regular course. For students who were placed into and completed the remedial course, large gains were found from precourse TSWE scores to postcourse TSWE scores. These findings support the placement uses made of the TSWE by the University of Houston. The evidence strongly suggests that students with low TSWE scores are unlikely to succeed in the regular introductory composition course and are likely to profit from the instruction provided in the remedial course. The following are appended: (1) Regression of Observed Retest on Observed Initial TSWE Scores Under Conditions of No True Change; and (2) Tables.