Variables affecting the sustained implementation of evidence-based practices are receiving increased attention. A descriptive analysis of the variables associated with sustained implementation of First Step to Success (FSS), a targeted intervention for young students at risk for behavior disorders, is provided. Measures based on a conceptual model of sustainability were used with personnel from 29 schools from 13 Oregon school districts to describe variables that promote the sustainability of FSS. Results indicate that 28% of the school districts continued to implement FSS up to 10 years after initial implementation. Six critical features were perceived by school personnel to promote sustainability: (a) dedicated resources, (b) training and orientation activities, (c) district-level coordination, (d) selection of students who are a good fit for the intervention, (e) highly qualified coaches, and (f) administrative support. Clinical relevance and future directions for research addressing sustainability are presented. (Contains 4 tables.)