An indicator is a gauge or sense that allows a person to draw a conclusion. Because teacher leadership is so vaguely defined in both research and practice, indicators can assist teachers in using their perceptual knowledge to recognize and define teacher leadership. This article reports the findings of a statewide study conducted to better understand which indicators of teacher leadership Illinois teachers consider strong and which indicators they consider weak. The study, which compared teachers' perceptions across five teacher characteristics and three school demographics, was originally published as two separate articles in two different state-level journals. Across all comparisons, the study's findings revealed "expertise" and "credibility" as the two strongest indicators of teacher leadership, with "frequency" running a close third. "Variety" and "connections" fell somewhere in the middle, and "credentials" and "scale" emerged as the two weakest indicators.