The diagnosis of tuberculosis is an increasingly important problem confronting the clinical microbiology laboratory as well as hospital epidemiologists. The inherent delays in conventional laboratory procedures for the isolation and susceptibility testing of M tuberculosis may contribute directly to the spread of tuberculosis. Application of newer methods that are more rapid is essential if the spread of tuberculosis is to be limited. Hospital epidemiologists and clinical microbiology laboratories should work together to critically examine all of their current procedures for tuberculosis and take steps to correct or improve all omissions and delays in mycobacterial tests ordering, collection, testing, and reporting.