In 1996, Danielson proposed 22 criteria that formed a framework for teaching. The framework, according to Danielson, may be used for supervision and evaluation of teaching, teacher reflection and self-assessment, peer coaching, and mentoring. The framework represents a modification of and extension of the 19 criteria that form the PRAXIS III®: Classroom Performance Assessments. The purpose of this study was to determine the appropriateness of the 22 criteria for use with beginning teachers as well as experienced teachers. Stratified random samples of 3,000 teachers and 1,000 principals were mailed the 22 criteria and asked to make two judgments for each criterion. They were asked to judge the importance of each criterion for the effective classroom performance of all teachers and to judge the importance of each criterion for inclusion in a teacher training and development program. Judgments were made on five-point rating scales. A total of 1,589 surveys (40%) was returned (1,133 teachers and 383 principals indicated their employment status, 73 respondents did not). The results indicated that, overall, the teachers and principals believed that the criteria were important to a teacher's effective classroom performance and were important for inclusion in a training and development program for teachers. Analyses by experience level confirmed the overall findings. The results of other subgroup analyses are included in the body of the report.