Early career teachers (ECTs) are potential resources for educational innovation and development in schools. Innovative professional potential (IPP) emerges in interaction between ECTs and their school ecology. Using semi-structured timeline interviews, we explored 105 IPP experiences of 19 ECTs in the Netherlands, aiming to understand when and how IPP emerges in the school, and to obtain a first grasp of how it can be stimulated. We categorised typification, location and professional interests and explored interaction processes with persons and affordances in the school ecology. Findings showed that ECTs initiate and perform innovative tasks and activities mainly at school or subject department levels. These tasks and activities are mostly social in nature or focused on educational development, while including a wide range of professional interests. Rather than one specific interaction with a person or an affordance, accumulations of restricting and stimulating interactions appear important for how IPP emerges. This paper concludes that it is crucial to consider ECTs capable of exercising the full range of teaching activities from the start of their career, and to share responsibilities among professionals in the school during ECTs' induction. These practices can help to increase educational quality and prevent teacher attrition.