This 2-year qualitative case study examined factors influencing implementation and sustainability of collaborative problem-solving programs. One selected elementary school served as the focus site. Using a participant-observer field-based approach, data were collected via observations, interviews, mute evidence, and field notes. During Year 1 of the study, implementation integrity was high, participants' perceptions of the process were positive, professional collaboration was enhanced, students' academic and behavioral concerns were effectively addressed, and special education rates were reduced. However, successful implementation was not sustained during Year 2 following a dramatic reduction in support from the school district. Analysis revealed district-level decisions exert a significant and cascading effect on procedures, perceptions, and ultimately student outcomes. Within that context, implications for practice are offered. (Contains 1 table.)