The purpose of this study was to examine the quality of the Program for International Student Assessment (PISA) 2009 school climate survey instrument and evaluate perceptions of secondary school principals' located in the United States about school climate using an Item Response Theory (IRT) methodological approach. In particular, this study sought to determine if the instrument's items are of sufficient psychometric quality to effectively measure schools' climate status in the United States. Collectively, results indicate the School Climate Assessment (SCA) scale is of sufficient psychometric quality to effectively measure schools' climate status in the United States. However, there are areas for which the instrument can be improved. Recommendations for improvement are provided.