Rationale: The tuberculin skin test (TST) has many sources of error. These can lead to predominantly false-positive reactions when used in low-risk populations. The Army deploys to areas considered at high-risk for tuberculosis (TB) infection, but often has limited contact with the local population. Objectives: We describe the investigation of eight pseudoepidemics of TST conversions in Army populations, five of which were associated with overseas deployments. Methods: Outbreak investigations of these pseudoepidemics consisted of several components: evaluation of active and latent TB surveillance data; review of medical records; investigation and interviews of active TB cases and their contacts; evaluation of materials and personnel screening procedures; and placement and reading of repeat skin testing. Measurements and Main Results: Initially reported risk of conversion in the outbreaks ranged from 1.3% to 15%. Repeat testing of converters (positives) found that 30 to 100% were negative on retesting. Several sources of false positive results were identified in these pseudoepidemics, including variability in reading and administration, product variability, and cross-reactions to non-tuberculous mycobacteria. Conclusion: Pseudoepidemics of TST conversions are a common occurrence after Army deployments and in Army populations. US Army forces generally have a low risk of TB infection resulting from deployments due to limited exposure to local nationals with active TB, and universal testing in this population has a low positive predictive value.