A small proportion of students do not benefit sufficiently from standard intervention protocols, and require more intensive, individualized instruction. Data-Based Instruction (DBI) has a strong evidence base for addressing students' intensive academic needs, yet it is not widely implemented. In this study, we explored the usability and feasibility of a professional development system to support teachers' use of DBI in writing. Data analyzed using a mixed methods design revealed that teachers perceived supports such as coaching as facilitators of DBI implementation, whereas access to materials and external factors such as time conflicts presented challenges. Teachers made statistically significant growth from pre- to posttest on a measure of DBI knowledge and skills, implemented DBI components with fidelity, and reported that time spent on DBI activities decreased each week, supporting its usability and feasibility. Findings suggest that DBI is usable and feasible when teachers are provided ongoing professional development supports. [This paper was published in "Elementary School Journal" Dec 2020 (EJ1283309).]