Tuberculosis has become a global problem responsible for the deaths of millions of people each year. In 1993 WHO declared tuberculosis as a global emergency to heighten public and political awareness. The development of drugs against Mycobacterial infection especially against tuberculosis has been quite rapid during the past 50 years. According to some fairly reliable evidence the initial drug resistant in India is mostly to Isoniazid of varying order but below 20% followed by Strepromycin (below 10%) and Refampicin (around 1 %). During the recent years certain molecular techniques e.g. IS 6110, probes based on 1081 Insertion sequences and direct repeat probes have started playing important role in investigating the epidemiology of different infectious diseases (e.g. tuberculosis) for designing suitable control strategies.