This study investigated university teachers' perspectives on their change readiness to implement education for sustainable development (ESD) through their participation in a problem-based learning (PBL) pedagogical development (PD) program. Theoretically, the study connected a systems-thinking approach to change readiness literature and proposed a four-dimensional conceptual framework, including intrapersonal, relational, and environmental dimensions. Q methodology was adopted to collect and analyze data both qualitatively and quantitatively. Four significantly different viewpoints emerged among the 25 participants regarding what they considered most important for their change readiness towards ESD, namely (1) improvement of teaching and learning performance, (2) personal learning and conviction, (3) applying PD learning to practice, and (4) student learning engagement and professional practice. Revealing a complex and interrelated connection between the four dimensions of change readiness, these results also observed university teachers' expression of learning gains and engagement in prospective change. Nevertheless, such change readiness was mainly within their micro teaching practice environment, with little anticipation of commitment to a wider institutional scale of change. Such restrictions on their change readiness were attributed to constrained institutional conditions and supports for long-term improvement. Results of the study suggested that it is essential to facilitate both individual awareness and efforts, as well as institutional readiness for the goal of implementing ESD in higher education (HE). In this regard, both systemic and systematic professional learning activities are recommended.