The study described in this report investigated the effects of field-based reflective practice on preservice teachers' sense of self-efficacy. Subjects in the study were 24 senior elementary majors participating in a 4-week field experience. Twelve students were assigned to the experimental school and 12 were assigned to two control schools. Each school had a graduate teaching assistant (GTA) who observed the preservice teachers during selected teaching experiences. In addition, the GTA in the experimental group conferenced extensively with each preservice teacher after each observed lesson to help, through coaching episodes, make sense of problematic situations. Biweekly, students in the treatment group were brought together for networking where they could recast, rethink, and bring new meaning to their practice. Pre- and post-measures of subjects' self-efficacy were obtained using the Teacher Efficacy Scale, open-ended questionnaires, and reflective journals. Results suggest that sharing experiences and strategies with cooperating teachers, peers, and the GTA helped subjects in the treatment group become self-assured reflectors. The sharing also had a significant positive impact on preservice teachers' sense of self-efficacy. (Contains 9 references.) (LL)