In this study, we discuss findings from a small-scale project evaluating an in-service teacher training programme focused on "perspective transformation" in early childhood education and education for sustainability (EfS). A bespoke professional development programme was developed for Turkish early childhood teachers, based on a variety of Mezirowian-inspired adult education activities. Data were gathered using a mixed method research design, from 24 early childhood educators, through learning diaries, a Learning Activities Survey and follow-up interviews. Initial findings illustrate the range of transformations possible in the teachers' perspectives during and after the training workshops. Influential factors in facilitating perspective transformation are shown to be the content, structure and sequencing of the training, and peer support. We conclude that transformative learning techniques offer a viable framework for engaging practicing early childhood teachers with EfS and also discuss implications for teacher preparation in both areas.