In 1969 he married Alicia Koplowitz. After that, he and his cousin started working for Fomento de Construcciones y Contratas, the company founded by Alicia's Father. By the year 1976 he became CEO of the company.
Driven by the talent of Cortina and Alcocer, and through a never before tried diversification from its core building Business into other sectors, the company grew greatly in value over a period of 18 years. This growth was accomplished in spite of the Spanish crisis that took place between the years of 1973 and 1985. The company that was having a turnover of 1,000 million pesetas when Alberto joined it, became a Diversified group of over 30 companies, with a total turnover of close to 300,000 million pesetas and a valuation of USD 3b.
In 1978, both Albertos acquired 5% of Banco de Fomento, belonging to Banco Central. Three years later, they acquire a significant stake in Portland Valderrivas, a cement company owned by Banesto, on which they placed Alberto Cortina's brother, Alfonso Cortina, as head of the company.
In 1982 they acquired Banco Zaragozano. Later, in 1988, together with KIO Group they created Cartera Central which had a significant stake in Banco Central and two seats on its board of Directors. They tried to take over the bank Banco Central but were blocked in their attempt by the Government due to anti-monopoly rules. Banco Zaragozano was valued in USD 15m at acquisition and they sold it for over USD 2b to Barclay's Bank in 2003.
In 1998, both "Albertos" took at a controlling stake in ACS Group, today's largest construction and services group by revenues, with sales of EUR €40b worldwide in 2015. Among its subsidiaries are the German construction company Hochtief, Australian conglomerate CIMIC Group, Spanish construction company Dragados, Spanish electrical engineering Cobra and waste management company Urbaser. The executive chairman of ACS, Florentino Perez is also the chairman of Real Madrid Football Club.
In 2000 he married Elena Cué, with whom he had a daughter in 2006.
In 2010 Forbes magazine included Alberto Cortina in their billionaires list ranking as the 828th wealthiest man in the world.
In June 2015 Banque de Dakar starts to provide financial services at its headquarters in the capital of Senegal and providing banking services at a Pan African level focusing in the UEMOA region. The bank is controlled by the BDK Financial Group led by Cortina along with various relevant shareholders. In February 2016 Alfredo Sáenz Abad is appointed President of the bank and in March he acquires 5% of BDK's shares.