This study examined whether adding student and teacher survey measures to existing principal evaluation measures increases the overall power of the principal evaluation model to explain variation in student achievement across schools. The study was conducted using data from 2011-12 on 39 elementary and secondary schools within a midsize urban school district in the Midwest. The research team used the results of the district's Tripod student and teacher surveys to construct six school-level measures of school conditions that prior research has shown to associate with effective school leadership. The study finds that adding the full set of six survey measures as a group results in statistically significant increases in variance explained in mathematics and composite value-added outcomes, but not in reading. A stepwise regression procedure identified two measures--instructional leadership and classroom instructional environment--as an optimal subset of the six measures. This evidence indicates that student and teacher survey measures can have utility for principal performance evaluation. The following are appended: (1) Literature Review; (2) Data and Methodology; (3) Supplemental Analysis; (4) Descriptive Statistics and Regression Coefficients for the Principal Evaluation Measures; and (5) Tripod Student Perception Survey.