The decision as to the patient being clinically tuberculous (ill with tuberculosis) must rest on the consideration of the clinical history and the results of the physical examination. It is maintained by some that the subcutaneous tuberculin reaction is _more rapid in onset_ and _more marked in degree_ in cases of _recent_ infection. On the other hand, the test is negative in a certain proportion of far advanced cases. Occurrence, then, of a subcutaneous tuberculin reaction does not indicate necessarily sanatorium or institutional treatment; neither does it absolutely indicate the necessity of tuberculin treatment. The decision rests on the consideration of all the clinical features of the case. _In the absence of any symptoms or physical signs of disease_, a reaction should call for regulation of every day life, tending to increase the state of general resistance (improvement of nutrition, etc.) frequently without discontinuance of work. The occurrence of reaction, _in the presence of slight symptoms or physical signs_, calls, according to individual condition, either for home treatment with or without discontinuance of work, or sanatorium treatment. 14. INDICATIONS FOR THE SUBCUTANEOUS TUBERCULIN TEST: The following considerations should guide its employment: 1. A thorough study of the history, thorough physical examination, examination of sputum (if any) give sufficient data for a reliable diagnosis in the vast majority of cases. 2. Cases, with uncertain symptoms or inconclusive physical signs, pointing to possible existence of tuberculous infection, may be treated as "suspicious" cases (without resorting to subcutaneous tuberculin test), the treatment consisting of rearrangement of mode of life, diet, work, etc., that would tend to increase of general resistance of the patient. This can and should be done in the vast majority of suspicious cases. 3. The subcutaneous tuberculin test is indicated in cases in which, in the absence of conclusive symptoms or signs, an absolutely positive diagnosis is desired; then the test should be applied, with the consent of the patient, _after all other methods of diagnosis are exhausted_ (thorough study of the case, thorough physical examination, repeated examinations of sputum, etc). 4. The focal reaction (the reaction pointing to the seat of the disease) occurs in about 1/3, or less, of the general reactions following the subcutaneous tuberculin test; this enhances the value of the test in some cases where a focal reaction would clear the diagnosis.