The Constituent Assembly debates inform us that the duty of the Union towards the States under Art. 355 of the Constitution was incorporated in order to justify the drastic shift in the balance of Union-State relations caused by emergency action under Art. 356. An analysis of various legal authorities’ interpretation and employment of Art. 355, however, reveals a gradual but stark evolution in its character, one which significantly widens the scope of Union action contemplated by it. This paper ventures an explanation for this departure but does not criticize it, as the current position may still be used beneficially. With a substantially wide range of Union interference in the States’ domains amenable to be validated or invalidated on the touchstone of Article 355, however, the concern arises that such interference- and the calls for it– may often be tainted with mala fides or political unscrupulousness. To allay this fear, it is necessary that the constitutional ideal of co-operative federalism be taken note of with fresh vigour. The plea is not utopian as was recently illustrated by the Union’s responses to the Karnataka Governor’s recommendations for emergency action under Art. 356.