English as a foreign language teachers' associations (henceforth ELTAs) act as empowering platforms for English Language Teaching (ELT) professionals (Lamb, 2012), and yet the contributions of ELTA leaders have not been widely investigated in the fields of second language acquisition and language pedagogy. In order to fill this niche, a qualitative interview study explored the professional trajectories of successful teacher trainers. The paper gives an account of the motivation for continuing professional development (CPD) through the turning points in these professionals' early careers. The findings suggest that there are some similarities behind the motivating factors for CPD and the increasing participation in social spheres (Lave & Wenger, 1991) leads to professional growth. Moving from the periphery towards the centre in a Community of Practice (CoP) the participants of CoPs become knowledge providers. The results reveal that after members have reached their own plateau and can no longer grow professionally in a particular CoP, they either move on to a different, often more challenging CoP and often belong to different CoPs and even end up as the leaders of ELTAs. Limitations and further research suggestions are included at the end of the paper.