This paper details how a 7-month reading-focused professional development initiative, centered on the assessment-to-instruction cycle, supported teachers' growth by combining small group sessions with related individualized literacy coaching. Analysis of participants' experiences revealed the significance of differentiated professional learning in supporting teachers' abilities to first modify their reading assessment practices, and then modify their reading instructional practices in response to their students' identified needs. Importantly, requisite to supporting teachers' diverse needs and interests was differentiating the content, process, and expected outcomes of this professional learning initiative. Notably, this study documented how "walking the talk" with respect to differentiated learning, enhanced teachers' abilities to provide responsive differentiated instruction for their students. Implications include the use of students' reading assessment results as a catalyst for teacher change and use of proximal goal setting following collaborative small group sessions to delineate the differentiated foci of concurrent classroom-based coaching.