The paper reports the findings of a project that assessed the benefits of peer feedback as a formative assessment intervention for postgraduate international learners in the United Kingdom. The aim was to improve participants' understanding of quality in academic writing, and hence improve the summative assessment scores, by improving the quantity of feedback received in a collaborative learning environment. The project utilized the action research methodology and qualitative methods to recommend effective practices for peer assessment. Research findings highlight that although there was no substantial increase in the average score for the groups that received peer feedback, improvements in summative scores for the higher ability students were observed. All the learners agreed that the peer feedback should be made a permanent feature of the program; they also highlighted that the main barriers in giving feedback were lack of experience and hesitation in critiquing peer's work. It is recommended that peer assessment is included as a regular feature of postgraduate programs but with adequate tutor planning and student preparation. Additional strategies to encourage engagement of postgraduate students with the "Peer Feedback" are required to demonstrate improved results across all ability levels.