Virtual microscopy is being used in medical schools to teach histology and pathology. It is also being used in resident education, in-training examinations (dermatology), and certification examinations (pathology). There are, however, few studies comparing its diagnostic accuracy and acceptability compared with traditional glass slides. This study sought to compare residents' abilities in diagnosing dermatopathology disorders in 2 image formats (traditional microscopic slides and whole mount digitized images) and to assess their perceptions of virtual microscopy in dermatopathology. Residents in dermatology and pathology training programs at 14 institutions were given a randomized combination of 20 virtual and glass slides and were asked to identify the diagnoses from multiple foils. They were then asked to give their impressions about the virtual images. Descriptive data analysis and comparison of groups using Pearson chi(2) and Fisher exact tests for categorical variables and Student t test for continuous variables were performed. Residents in dermatology and pathology performed similarly in diagnosing dermatopathology disorders using virtual slides or glass slides (mean [SD] correct for virtual versus glass, 5.48 (1.72) versus 5.57 (2.06); P = .70). The order of administration of virtual versus glass slides did not affect the percentage of questions answered correctly. Most residents supported the use of virtual microscopy as a learning aid, whereas fewer favored its use in testing (79% versus 44%, respectively). Residents performed similarly in making dermatologic diagnoses using virtual slides compared with glass slides despite the residents' preference for the latter.