Studies on collaborative writing practices are not new (Reynolds, Wooley, & Wooley, 1911), neither is the interest in collaborative writing supported by computers (Sharples, 1993). With the advent of Web 2.0, there has been an immense increase in research examining web-based collaborative writing, particularly in L2 contexts (Cho, 2017; Kessler, 2013; Sevilla-Pavón, 2015; Yim & Warschauer, 2017). The present study follows this research path by analysing perceptions of technology-assisted collaborative writing as well as collaborative writing processes in a Spanish for specific purposes class. Eight students from the Cyprus University of Technology (CUT), Department of Communication and Internet Studies, participated in the study. The data were elicited over five collection times, which included two digital artefact creations (an out-of-class and an in-class collaborative writing task), a pre-Questionnaire (preQ) and post-Questionnaire (postQ), and a focus group interview. The analysis of the data revealed that the students' perceptions are mediated by task type, which in turn also affects collaborative writing patterns being the out-of-class activity the one that presents a wider variety of writing styles as well as a more balanced participation among students. [For the complete volume, "Tertiary Education Language Learning: A Collection of Research," see ED614100.]