This multi-method, qualitative study seeks to examine issues surrounding the purposes and roles of the written feedback provided by Malaysian lecturers in a private university on assessed student assignments written in English in two subject disciplines – English and science. The overall purpose of the study was to investigate the views and practices of staff and students that relate to provision and reception of assignment feedback and, in particular, their perceptions relating to its role and effectiveness. An on-going issue is that although formative feedback is supposed to enhance students’ learning, students are often unable to interpret and apply the feedback that they receive. Recently, sociocultural theorists have advocated the incorporation of students’ own views about feedback back into formative assessment to improve the effectiveness of feedback and further assist students to self-regulate their learning (Murphy, 2000; Nicol, & Macfarlane-Dick, 2006; Scott, 2005). Ten lecturers (five English and five science) were recruited through their participation in an initial survey, which was followed by a case study approach using multiple data collection methods. First the lecturers were interviewed individually and their students were interviewed in groups to obtain their beliefs towards written feedback in general. Then, using think-aloud protocols, each lecturer was observed providing written feedback on one or three students’ assignments. This was followed by interviews with those students whose assignments were marked during the think-aloud sessions to obtain their responses towards their lecturers’ feedback. Finally, summaries of these student responses to the feedback were then presented back to the individual lecturers to elicit their responses and reflections. The approach to the analysis of the data was a combination of grounded theory and thematic analysis (Glesne, 2011). The thematic findings were then subject to further analysis using socio-cultural theory, specifically the concepts of Zone of Proximal Development and Activity Theory. The main findings suggest that, although the English and science lecturers had pre-conceived beliefs about what constitute good written feedback practice, four contextual factors: the policies relating to assessment and feedback of the local and partner universities, the lack of training among the lecturers, the lack of training of students in Academic Writing and the students’ poor English proficiency caused the lecturers to modify practices of their provision written feedback in ways that diverged from their beliefs. It was also found that the lecturers’ feedback did not match students’ expectations in terms of the purposes, types and foci of feedback, and the amount of guidance preferred in the feedback. However, when the students’ responses were made revealed to the lecturers, some lecturers decided to incorporate students’ views into their feedback practices. My findings suggest a number of contributions to the field of teacher cognition, second language instruction and social-cultural theory. While few studies have examined the influence of contextual factors on teacher cognition, this study revealed the role of contextual factors in moulding lecturers’ beliefs. Other potential contributions include implications for the practical application of written feedback, expanding the existing activity theory framework to examine conflicts caused by the different beliefs and practices within an institution, and the application of think-aloud protocols to the investigation of teacher cognition.