This article summarizes a dissertation study designed to determine the effectiveness of instructional interventions that focus on proofreading and editing skills of first-year college students enrolled in business communication courses. The study used a pretest-posttest quasiexperimental control group design and collected data from 56 participants based on the results of the Grammar and Mechanics Diagnostic Assessment for two experimental groups and a control group. The results of the project were compiled and analyzed using descriptive statistics and a repeated measures analysis of variance. (Contains 3 figures and 2 tables.)