The literature on school improvement is littered with sombre reports of how ICT-mediated innovations have failed to create impact on teaching and learning. Even when evidence-based successes are palpable, they are sporadic and rarely sustainable. Against the backdrop of the litany of such studies, this paper reports the case of a primary school in Singapore that has a decade-long experience in integrating, growing and sustaining ICT-mediated innovations. By distilling the influences underpinning its integration, the article aims to make a contribution to the theorisation of educational leadership situated in the context of technology-mediated reform for student-centred learning. Using a complexity lens, this paper looks at how school leaders, together with other autonomous actors in its ecological system, foster the favourable conditions for sustainable technology-mediated pedagogical reform. Data of the study are drawn from interviews, observations of lessons, fieldtrips and professional development meetings as well as document analysis. Based on the findings, a complexity-informed model for technology-mediated reform is devised and its implications discussed. They include the need to cultivate the following within and across the subsystems of the school: (a) ecological awareness; (b) collective reflexivity on practices and implementations; (c) creating alignment; and (d) capacity to forge ecological coherence.