Cusi started his career in shipping. He joined the Aboitiz Shipping Company in 1973 as Assistant Comptroller. He worked his way up to become the company's and its subsidiaries' Credit Collection Manager, Purchasing Manager, Passage and Stevedorial Manager, and Trucking Manager. By 1977, he was promoted as Assistant to the President, and eventually as Assistant Vice President in 1979, Vice President in 1983, and General Manager and EVP in 1985. He was Senior Vice President and Director before resigning from the company in 1990. Cusi then ventured into his own shipping, logistics and distribution businesses. He founded the Starlite Ferries which offers roll-on/roll-off ferry service between his home province Mindoro and Batangas, as well as Aklan. He is also the President and founder of Starlite Cargo Xpress. He also entered the retail business with his own chain of convenience stores called Quick Stop. With his broad experience and knowledge in the shipping and transportation industry, he was invited to join government service in 2001 as General Manager of the Philippine Ports Authority during the first term of President Gloria Macapagal Arroyo. As head of the port authority, he is credited with having introduced and developed seaport terminals throughout the country. He was also the main project head of the Strong Republic Nautical Highway System of the Arroyo administration. In 2004, Cusi was then assigned by Arroyo to lead the Manila International Airport Authority. As an airport manager, he was responsible for finally opening the long-delayed Ninoy Aquino International Airport Terminal 3 in 2008. Cusi assumed leadership of the Civil Aviation Authority of the Philippines in March 2010. Among his contributions to the agency is regaining the Category 1 status of the Philippine aviation industry from the Federal Aviation Administration which finally allowed Philippine carriers to fly to the United States and Europe. Cusi resigned from CAAP in December 2010 and returned to his private businesses. He served in the board of Intex Resources Philippines which has a nickel and cobalt mining project in his home province of Oriental Mindoro. He was also involved in Double Concept Investments, Ltd. prior to his return to government service under President Rodrigo Duterte on June 30, 2016.
