Pathology training programs typically retain teaching files of classic and unusual diagnostic cases. Since diagnostic criteria and terminology are mutable, we reviewed a surgical pathology teaching archive to determine if the materials continued to be acceptable for educational purposes. Each case (from 2001-2003) consisted of 1 to 3 slides and a 3 x 5 card with clinical information and the diagnosis. Cases were reviewed at a daily faculty consensus conference and categorized as follows: no diagnostic change; diagnosis added; or changed diagnosis. Slides were entirely missing from 79 (35.0%) of the 226 cases reviewed. Of the remaining 147 cases, 28 (19.0%) required additional clinical information and/or slides. The final disposition of the 147 cases was as follows: diagnosis unchanged, 126 (85.7%); diagnosis added, 15 (10.2%); and diagnosis changed, 6 (4.1%). Teaching files should be subject to prospective and retrospective controls to preserve the quality of the educational experience.