Using social constructivist theories of adult learning and complexity thinking perspectives, a long-term, multi-tiered professional development (PD) programme was designed, implemented and evaluated at Qatar University. This qualitative study explored the systems of influence on 24 university teachers’ professional agency for learning and leading sustainable change throughout their participation in the programme. Within the context of educational change, university teachers’ professional agency refers to their ability to exercise control, take stances, make choices and exert influence in ways that impact their learning and leading sustainable change. Using multiple sources of data, participants reported supports and constraints to their professional agency within multiple systems. These systems of influence included factors within the personal, PD programme, department/college, and university systems. Findings revealed variations in university teachers’ willingness and capacity to examine previously held beliefs, design innovative pedagogies, and become change agents. The findings underscore the notion of emergence as an explicit characteristic of learning and leading change within and across complex systems. Future iterations of the programme, and similarly constructed programmes in higher education contexts, should consider the systems of influence on university teachers’ professional agency for learning and make concerted efforts to support their ability to lead sustainable change.