This case study investigates the effectiveness of paraphrasing guidelines taught in a graduate academic and research writing class at a Thai university. It evaluates the use of paraphrasing strategies, as taught through the guidelines, by students when paraphrasing English-language sources. The assessment considers the students' utilization of these strategies while employing all available resources, which is the typical approach in academic writing. A pretest/posttest task was administered to determine the improvement, if any, in key paraphrasing strategies among the 12 students enrolled in the course. Background information was collected through a questionnaire before the pretest, and face-to-face interviews were conducted after the posttest. Although students demonstrated significant improvement in almost all strategies, it was identified that explicit instruction should be increased, particularly in skills related to reordering words, such as changing sentence structures, as well as adding text by conveying the same meaning in their own words. Additionally, a moderate emphasis on instruction could be placed on strategies related to changing words, such as finding synonyms. Other skills, notably citing, require no further emphasis. Based on the results, recommendations are provided for enhancing the guidelines, and suggestions are offered for instructors looking to refine their own writing courses that incorporate paraphrasing.