This study presents a Context Based Participatory Professional Development path of early childhood educators and assistants in an early years centre located in Lisbon, Portugal, aiming at the contextualization of Pedagogy-in-Participation. Processes of contextual professional learning and praxis transformation are conducted and open up horizons to new children's learning and teaching practices and thus support the reconstructions of pedagogical praxis and professional identities. It asserts that a deep understanding of participatory pedagogies is reached when professionals experience participation in their professional development processes. The aim is to develop participatory professional experiential learning that inspires practitioners to develop participatory pedagogies with children. This study sits in praxeological research and documents processes and achievements on praxis transformation, highlighting the importance of assistants' participation in reconstructing educational environment and creating collaborative educational teams.