This study examines the relationship between supervisor evaluation of classroom performance and exit portfolio ratings of candidates enrolled in the Professional Immersion Master of Arts in Teaching Program, a partnership between Johns Hopkins University and Montgomery County (Maryland) Public Schools. This graduate-level teacher preparation program provides candidates with more than a year of internship experience, a high degree of supervisory support, and significant financial assistance. The school district provides tuition assistance in return for a 3-year commitment by candidates to teach in the district. All candidates are evaluated several times during their internships by a university supervisor and must create and present a portfolio, which is scored by an independent panel of educators. (Contains 4 tables.)