There is growing research aimed at translating parent-mediated interventions into Part C Early Intervention systems to examine the effectiveness and reach of these models. Although research to date suggests that Early Intervention providers deliver parent-mediated intervention near fidelity, current fidelity reporting practices make delivery difficult to discern. Understanding how parent-mediated interventions are delivered and adapted in a more nuanced manner, including fine-grained intervention delivery and adaptation processes, is important and may increase our understanding of how well these models are aligned within Early Intervention systems. The current study examined the delivery of an evidence-based parent-mediated intervention, Project ImPACT, when delivered by Early Intervention providers and examined their intervention fidelity, the decisions they weighed when delivering Project ImPACT, and reported adaptations to Project ImPACT. Results from 24 providers demonstrated, on average, higher fidelity in response to consultative feedback but notable variability across providers. Preliminary qualitative data highlighted that many events arose within sessions that drove providers to augment their delivery of Project ImPACT. Results suggest the importance of carefully examining how and why providers deliver evidence-based interventions within Early Intervention systems, and the impact of these decisions on fidelity metrics and service outcomes.