The ideal period for implementing environmental education or education for sustainability is during the early childhood years. The educational context of playgroups can be a platform for both children and their parents to learn together and together engage in early childhood education for sustainability (ECEfS), however there is a paucity of literature examining ECEfS within Australian playgroup contexts. The Little Explorers Playgroup (LEP) is a facilitated playgroup located in a sustainable living centre in Sydney, Australia, and provides opportunities for children and their parents to engage in ECEfS. The study purpose was to evaluate the effect of the LEP on the participating children and parents' environmental attitudes and behaviours. This qualitative study was designed as a single critical case study employing semi-structured telephone interviews conducted with twenty-three participants, including three LEP playgroup facilitators and 20 parents. The data generated by the interviews was analysed thematically and the findings indicated that the LEP empowered and positively transformed both the children and parents' environmental attitudes and behaviours. This was evident through the children and parents' adoption of more environmentally responsible attitudes and behaviours. The findings demonstrate that playgroups may be an untapped opportunity for facilitating community change towards sustainable living.