Ever since the time of Hippocrates attempts have been made to classify tuberculosis. Not until the 19th century was a clear clinical division made between acute and chronic forms (Fournet, 1839); later there was a tendency to describe these forms as ‘galloping consumption’ and ‘consumption’; to-day they can be accurately described, not only on clinical grounds, but pathologically, radiologically and pathogenetically as ‘malig nant primary’ and ‘advance secondary’. The first clinico-pathological classification was by Bard (1898, 1927). He described four forms: parenchymatous, interestitial, bronchial, and post-pleuritic. Bard postulated the still valid principle that every form must have ‘per son evolution, son pronostic, sa marche generate, une veritable unite lui.
