This study examined the concerns and confidence of 10 educators (9 elementary and secondary school teachers and 1 school principal) as they adopted naturalistic assessment procedures. Participants enrolled in a 4-month graduate course and implemented various literacy assessment procedures in their classrooms. Data were collected through the Stages of Concern Questionnaire (SCQ), interviews, confidence ratings, written narratives, and field notes from class discussions. Group results from the SCQ indicated a shift from "self" to "impact" concerns. Confidence ratings increased over time; narratives showed that participants were confident in their abilities to implement naturalistic assessment but were not confident about the success of naturalistic assessment beyond their classrooms. Factors that influenced confidence were identified and categorized as: (1) teacher uniqueness; (2) professional development; (3) significant others; and (4) teaching environment. The participants felt that naturalistic assessment empowered them as well as their students. Portraits were developed for each participant that demonstrated the importance of a supportive teaching environment to the success of naturalistic assessment. (Contains 1 table, 3 figures, and 15 references.) (Author/SLD)