During his office in the National Congress and from the seat of the Presidency of the Republic, Pellegrini devoted himself to estate matters. Ideologically, he took part in the argentine liberal heterodox current. Possessing a realistic spirit, he tried hard to put into practice the principles of neo mercantilism. He conceived leading in function of the economic development and the thought of free-trade as one of the most intelligent ways of protection the British industry during the XIX century. He limited his economic policy to these points: a) continue fostering the agricultural and cattle industry; and b) promote, through national protectionism, the rise of manufacturing industries, especially those private enterprises which used a first rate argentine raw material. The national industry being organized, and the internal market settled, any kind of protection, which is always limited in time, ceased. Then, a new stage began, that of free trading and the nation would therefore enter the international market.