She worked at the Trust from 1983 to 2019 including two assignments as interim president and chief executive officer and 30 years as Director of the Getty Foundation.

She was a devoted camper at Camp Walden in Denmark, Maine, where her daughter, Anna, and her sister, Jane Marrow Bemis, also attended.

In California, she finished her doctoral thesis on the art patronage of Maria de' Medici (1978) after which she taught at colleges and universities in the Los Angeles area.

In 1982, she was hired as a consultant by the then nascent J. Paul Getty Trust to help vet senior staff being considered for the growing organization.

A notable achievement by Marrow was developing the concept for Pacific Standard Time: Art in L.A., 1945–1980 which was celebrated throughout Southern California in 2011-2012.

[3] Under her leadership, the foundation awarded $28 million in grants to dozens of cultural institutions across Southern California to tell the story of the Los Angeles art scene.

[6] Pacific Standard Time: LA/LA (2017–18) extended that collaborative model to fund exhibitions and scholarly research focused on Latin American and U.S. Latino art in Southern California.

[9][10] Over 27 years, the Internship Program has funded more than 3,000 students working at local arts institutions including museums throughout the southern California area.

Her tenure on the Board included membership on the Executive; Nominating; Local, National, and Global Engagement; Facilities and Campus Planning; and Honorary Degrees and Awards Committees.

In 2004, Marrow was part of the consultative committee that recommended to the Trustees Amy Gutmann for election as Penn's eighth president.

Marrow received the degree of Doctor of Humane Letters, Honoris Causa from Goucher College in 1983 where she gave the commencement address.