Doris Magsaysay Ho joined Magsaysay Maritime Corporation in 1979 and assumed the position of Chief Executive Officer (CEO) in 1981. Under her leadership and guidance, the company found its niche in the ship manning business. She believed that the quality of seafarers was paramount to the protection of vessel and cargo and, ultimately, to the ability of a shipowner to compete.

In 1986 the Company acquired the National maritime Corporation engaging in inter-island and near-sea trades for both dry and liquid cargoes. The company also organized Batangas bay Carriers, Inc., which operates a fleet of tanker barges on long-term charter to Shell. In the 1990s, Magsaysay maritime Corporation ventured into domestic tourism and further expanded its training capabilities. For example, Magsaysay Institute of Shipping was established. Further, Magsaysay Training Center offer free skills training and upgrading to deserving seafarers. It also offers safety courses, navigation and communications training, English proficiency and other language courses. It also runs a training vessel, the T.S. Hoho.

In 2003 Ms Magsaysay was the first Flipino to win the Socially Responsible Entrepreneur Award and in 2004 she received the entrepreneur of the Year Award.