This qualitative case study examined a critical, project-based clinical experience in a secondary education teacher preparation program, where university-based teacher educators, preservice teachers, and a school-based teacher educator collaborated to address authentic pedagogical challenges through a boundary-spanning partnership. Focusing on a week-long “problems of practice” project in a high school English language arts classroom, the study investigated essential skills and dispositions for mutually beneficial clinical experiences and explored tensions emerging during implementation. Findings revealed that effective boundary-spanning partnerships require participants to embrace discomfort and vulnerability while navigating institutional hierarchies. These insights inform teacher education programs seeking to design clinical experiences that equitably serve preservice teachers, mentor teachers, university faculty, and students.