Employing graduate students in undergraduate courses is common practice in higher education. This study focused on the concerns of graduate teaching assistants (GTAs) to learn how their work performance could be improved. GTAs (N = 158) at a major research university in Israel provided written recommendations for enhancing their work. Thematic analysis revealed 11 categories which were grouped into four main areas of concern: employment conditions, job definition, competency, and work management. Some GTAs' personal and job characteristics were found to be associated with the frequency at which the different categories of concern were mentioned. The findings have implications for actions that can be taken by higher education institutions to improve work conditions for GTAs with the aim of assuring the quality of their teaching.