This study analyzed data on students in three Ohio school districts who had completed grades 8 and 9 to determine which data elements were the most accurate indicators of students' failure to graduate from high school on time. The most accurate indicators varied by district and grade level, which underscores the importance of having school systems verify the accuracy of early warning indicators in their local contexts. School systems consider multiple factors when designing early warning systems, including the data available on students at different grade levels, the optimal cutpoints for the data elements, the consistency and accuracy of the indicators, and the possibility of using combinations of indicators for predicting failure to graduate on time. In short, the best indicators of failure to graduate on time for one district and grade level may not be the best for other districts and grade levels. [For the full report, see ED566958.]