This paper studies introduction and conclusion sections of papers produced by Spanish PhD Students in an academic writing workshop. Based on Swales's CARS model, the aim is to analyze the movements, steps, and substeps accomplished in the construction of the introduction (Carbonell-Olivares, Gil-Salom, y Soler- Monreal, 2009) and concluding sections (Yag y Alison, 2003). With regard to introductions, results of the study confirm, in line with previous studies, that movement 1 (M1) and 3 (M3) are considered compulsory by Spanish writers. Moreover, participants consider more important to establish the topic of the research than highlighting the significance and originality of the work. In the case of the conclusions, there is a presence of the three prototypical sections (M1-M2-M3). Nevertheless, the main focus in on the summary (M1) and the evaluation of the results (M2). [ABSTRACT FROM AUTHOR]