<p>Whilst outcomes for students on field trips to science centres or museums have been extensively studied, the informal professional development that teachers themselves may experience has been less examined. This study, based on semi-structured interviews with two participants, examines teachers’ experiences when accompanying their students on science field trips using Falk and Dierking’s (2018) Contextual Model of Learning (CML). This allowed for an exploration of the professional development teachers experienced and how various personal, sociocultural and physical contextual factors, as well as time, may have influenced these benefits. The interpretive analysis found that each teacher experienced a range of intellectual, attitudinal and behavioural professional development, as well as improved relationships with their students. All the contextual factors of the CML, as well as time, appeared to influence teachers’ experiences in inter-related and dynamic ways. Although all the factors of the CML were important for teachers’ development, the sociocultural interactions that teachers undertook seemed particularly significant. Observing the practices of other science professionals, as well as participating alongside their students in learning activities, were important for teachers’ development. This research determined that whilst field trips are organised for the benefit of students, they may also have an impact on the teachers who are accompanying them and therefore should be valued as important informal professional development opportunities. Although the CML was not designed for use in this context, it was demonstrated to be a useful framework in understanding informal teacher professional development.</p>