The worldwide increase in tuberculosis has stimulated a new wave of interest and research. Epidemiological studies have emphasized the close association between tuberculosis and poverty. Modern molecular techniques have given us a new insight into the way the disease is spread. Carefully planned and supervised therapy with well known and well tried drugs has shown that problems of multidrug resistance can be overcome without new and more expensive drugs. Some existing drugs are proving effective in antituberculous therapy. Immunotherapy may have a part to play, but results of controlled trials are awaited.