The focus of the study was an interest in discerning the relationship between grammar knowledge and its application for evaluating grammar development at different academic and professional stages. A 3-part questionnaire was completed by first and last semester Communication Sciences and Disorders (CSD) graduate students, and practicing speech-language pathologists (SLPs). The first section gathered data related to educational background, perceptions related to grammar knowledge, and recall of undergraduate instruction on grammar topics. A Grammar Test (GT), which reviewed typically developing grammar elements and sentence structures, and a Language Sample Analysis (LSA) comprised the latter two sections. With this data, the participants' grammar knowledge and its application in a language sample analysis were addressed. A correlational analysis was conducted to determine the degree of the relationship between the grammar knowledge students and SLPs demonstrated and their skill in applying that knowledge in a language sample analysis. The correlations for the first semester students and SLPs were moderate to strong and statistically significant (p less than 0.01). A weaker and non-significant relationship was found for the last semester students. No significant differences were noted between the groups' GT and LSA scores indicating that levels of education and/or years of experience were not factors in the students or SLPs' performance on these assessments. From an academic perspective, the students and SLPs' scores were below a passing grade for graduate students. The participants expressed confidence in their grammar knowledge yet seemed to have limitations in their knowledge of developmentally, predictable grammar structures. Reports of experience in grammar instruction at undergraduate and graduate levels revealed that the mean GT score was higher for CSD students who recalled receiving such instruction in a language development course. The SLPs identified formal assessments where scores are used for qualifying and documenting support services in academic settings. Analyses of the tests revealed that many grammatical elements and sentence structures, which develop in a predictable fashion, are not assessed on all the tests. As a result, the SLPs and students' dependence on formal assessments may have influenced their confidence in their grammar knowledge and skill in language sample analysis. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]