Purpose: The purpose of this paper is to consider an expanded vision of professional development for embedding education for sustainability (EfS) in a higher education institution. Through an exploration of a community of practice at the University of Tasmania, this paper examines how collaborative peer learning can sustain and promote continued professional development for staff in higher education who are committed to EfS as an educational paradigm. Design/methodology/approach: This research was conducted through a mixed methods investigation that involved participant observation and semi-structured interviews and focus groups. Data were analysed and grouped into themes that are discussed in the paper. Findings: This research reveals that personal values and professional identity were the two driving factors for continued engagement in a collaborative peer learning initiative. Despite institutional challenges and a lack of success of growing membership in the community of practice, participants found a level of job satisfaction and personal connection to the initiative and to each other that has sustained action and impact for this group. Originality/value: This work contributes an alternative voice to the professional development discussion around EfS. While most professional development activities are aimed at transferring knowledge to individuals and groups that are identified to lack awareness or capacity in a topic, this work highlights the need to include and foster safe learning spaces for continued professional learning. Particular attention is paid to the value of peer learning to support the professional development of sessional staff engaged in EfS.