Student research is an important pedagogical feature across the higher education lifecycle. Postgraduate taught (PGT) student research has received limited attention in the context of the diverse nature of the PGT cohort. Using Activity Theory, PGT student research is explored from the perspectives of differently motivated Master's students: students studying to progress to doctoral study and students studying a professional Master's to progress in their current career path. Similarities, differences, tensions and contradictions are analysed, revealing new conceptualisations of Master's research. The outcome of student research, the Dissertation, emerges as a recurring tension within the analysis. A call for a new dialogue on the applicability of the Dissertation for a diverse PGT cohort is made, as the traditional Dissertation may not best meet the needs of professional Master's students. The need to find better ways to disseminate PGT research is identified, given the potential for contribution to knowledge and practice.