Increasingly postgraduate courses are delivered online to meet professionals' demands for life-long learning. The research examined the efficacy of students critiquing each other's seminal work, by either direct exchange or via online fora, as a structured part of their formal assessments. A total of 377 students across three experimental and two control subjects were involved in this comparative study of pedagogy. Mixed methods research included comparing students' prior achievement with their achievement in these courses, qualitative interviews, and learning environment inventories. The research methods aligned and were statistically significant in finding that structured peer critiquing was more effective for students with lower or average prior achievement and led to improved perceptions of their learning environment. Forums were found to be a more subtle means of structuring critiquing and engagement than direct exchange; however, care is also needed to ensure online debate is incisive. Two revised pedagogical strategies are proposed.