The Council for the Accreditation of Educator Preparation Programs (CAEP), required evidence of reliability and validity of measures used in a university's Educator Preparation Program (EPP). This paper describes processes that provided this evidence for the Teacher Performance Assessment (TPA). Literature examined included Messick (1989), Linn (1980). The TPA, a state-wide requirement, was introduced early in the university's EPP. Components were taught throughout coursework and clinical practice. Rubrics were aligned with Interstate Teacher Assessment and Support Consortium (InTASC) Model Core Teaching Standards and Learning Progressions for Teachers (CCSSO, 2017). Candidates were introduced to the TPA and rubrics in the Teacher Education Handbook. Course assignments were aligned with the TPA. Assessed knowledge and skills were taught for mastery. Accommodations were offered for candidates with documented learning differences. Candidates were given the opportunity throughout their work on the TPA to receive feedback and to revise sections. Three cycles of data were: Fall 2016: N=56; Spring 2017: N=94; and Fall 2017: N=56. TPAs for Cycles 1 and 2 were identical. The TPA for Cycle 3 had been revised. The EPP consistently interpreted data from the four-point evaluation scale as interval-level. Construct and content validity and reliability evidence: Factor analysis results: Cycle I: seven subscales explained 76.76% of the variance. Cycle 2 seven subscales explained 73.9% of the variance. Cronbach's alpha reliabilities for Cycle I and II subscales ranged from a high of Contextual Factors: a=0.907; a=0.921 to a low of Analysis of Student Learning a=0.882; a=0.897. Reliabilities for Cycle II were High: Reflection and Self-Evaluation a= 0.881 and low Contextual Factors a=0.673. Inter-rater reliabilities, consistently high, were included and discussed in the study.