[2] Whilst on these travels he took courses on gold mining, sugar cane production, economics, labor relations, cooperativism, civil engineering and railway systems.

[5] The first board of directors of the newly organized National Federation of Coffee Growers of Colombia assembled in Bogotá on August 3, 1929.

Its first members were Mariano Ospina Vásquez, Alberto Camilo Suárez, Gabriel Ortiz Williamson, Carlos Caballero, Jesús del Corral and Mariano Ospina Pérez, the greatest dignitary in the History of the Federation, for whom the organization of the national coffee industry was one of his most serious and ambitious concerns.

At its adjournment Ospina was elected, by unanimous vote of the delegates, as “Gerente de la Federación” (General Director).

His main objective was to assist, finance, and educate the coffee growers while implementing an aggressive program to penetrate the world market and to successfully capture a substantial share of it.

Ospina's name was suggested for the 1946 elections to take advantage of the division in the opposing Colombian Liberal Party between supporters of Jorge Eliécer Gaitán and those of Gabriel Turbay.

With only three weeks remaining for the main election Ospina was appointed as the official Conservative party candidate for the presidency of Colombia.

During his administration Colombia reached its highest level of coffee exports, both in number of bags and as a percentage of the gross domestic product (GDP).

He was determined to fortify the nation's infrastructure and created Ecopetrol (Colombian Petroleum Company) and Acerias Paz del Río (the country's largest steel mill).

[14] During his presidency, on April 9, 1948, the liberal leader Jorge Eliécer Gaitán was assassinated in confusing circumstances by Juan Roa.

Ospina created the Colombian Petroleum Company ECOPETROL (Empresa Colombiana de Petroleos), the Telecommunications Company TELECOM, the Social Security Administration ISS (Instituto de Seguro Social), the petroleum pipeline from Barrancabermeja and Puerto Berrío, the hydroelectric dams of Sisga, Saldaña and Neusa, and established the Colombian Economic Development Plan under the direction of the Economic Mission of Professor Lauchlin Currie.