This study was conducted to determine the effect of remedial instruction in English usage upon writing competence in a college business letter-writing course. It was hypothesized that remedial instruction in English usage would not affect an individual's letter-writing achievements. Subjects were 50 matched pairs (IQ, Freshman English, grade, age, sex, year in school, and major study area) in four control and four experimental groups. Remedial instruction was given the experimental group only. Writing competence was measured at the end of the term on three in-class written letters, which were evaluated by three authorities using a letter-evaluation guide. Evaluators' ratings were subjected to an analysis of variance which showed no significant difference between the two groups. Since the three authorities varied significantly in their ratings, it was pointed out that teachers should be aware that judgment of letter-writing skills can vary considerably and that communication is a subjective topic. (Author/JF)