Based on the recommendations of the K-3 Assessment Think Tank, an assessment design team consisting of current and former educators and early childhood education scholars developed a kindergarten entry formative assessment (KEA) which was piloted in 193 classrooms during the first 60 instructional days of the 2014-2015 academic year. North Carolina (NC) intended the pilot to be a first step toward scaling-up to a full statewide K-3 formative assessment process. Over the course of the NC KEA pilot, the authors conducted case studies of eight pilot schools selected for their demographic representativeness of the total NC kindergarten student population. These case studies involved classroom observations and semi-structured interviews with pilot teachers, administrators, and instructional coaches. Following the case studies, an electronic survey that was open to all pilot participants was conducted. The purpose of this qualitative study was to gather teacher and administrator perspectives of the NC KEA and determine whether: (1) changes were necessary to the professional development provided for the assessment; (2) the content of the learning progressions were developmentally appropriate; (3) the documentation process worked within teachers' routine classroom instruction; (4) teachers found the assessment's data useful in driving their instructional decisions; (5) the assessment aligned with the curriculum and assessment practices currently in place within their district and school; and (6) there were characteristic patterns between schools and/or classrooms where the assessment was being implemented with fidelity and those where it was not.