Recent scholarly developments emphasise integrating insights from public policy discipline within the multilevel perspective (MLP) to understand sustainability transitions better. In this context, this article incorporates the concept of street-level policy entrepreneurs, specifically government-affiliated implementation agencies, within MLP to explain technology adoption and market creation when the technology is not cost-competent. The MLP framework is applied to analyse the case of the LED transition in India and highlight how a window of opportunity emerged in India, driven by global niche developments, favourable regime conditions and relevant institutional mechanisms. However, the high upfront cost of LEDs posed a significant challenge in utilising this window for niche-regime linking. This study demonstrates the critical role and activities of a state-affiliated implementation agency—Energy Efficiency Services Limited—in utilising this window of opportunity to accelerate the transition. It examines Energy Efficiency Services Limited's innovative implementation model that helped overcome the high upfront cost of LEDs, resulting in widespread technology adoption and reorientation of firm activities towards domestic manufacturing of LEDs in India. This study contributes to MLP scholarship by exploring the role of government in the later phases of the policy process and transition.@en