This article reports findings from 2 studies situated within a larger scope of design research on a professional development program, "Early Years," for Part C early intervention practitioners, working with families in home and community settings. Early Years includes online modules and onsite mentor coaching, and its development has been grounded in principles of adult learning, evidencebased elearning practices, and regulations for Web accessibility. The studies presented in this article focused on evaluating feasibility of the first online module within the Early Years program, EvidenceBased Practice, and its accompanying onsite mentor coaching component. Participants found most instructional elements to be helpful whereas rating the length of online sessions as less practical. Salient interview findings regarding the mentor coaching component included the importance of orientation and reference materials and incentivized professional development. This study contributes to the literature on early childhood professional development that includes a strong familyfocused component.