Despite over two decades of research, initial teacher education (ITE) partnerships remain problematic. Our study explores the development of a mandated ITE university-school partnership in Wales amidst significant educational reform. Through qualitative research, involving focus groups with 47 teacher educators from a university and 15 schools, we investigate their perceptions and experiences, focusing on shifts in professional roles and responsibilities. Our findings reveal disparities in the impact on the staff, including differences in changes to their roles and responsibilities, perceptions and experiences of agency and in the emotional effort required in the change process. We contend these findings have implications for all stakeholders involved in development of university-school ITE partnerships. In particular, the need for support for the development of individual and joint agency for all staff involved in partnership-building efforts. By shedding light on the complexities involved, we offer valuable insights for practitioners and researchers engaged in similar initiatives.