Eng was a corporate attorney with the firm Coudert Brothers, before helping to launch ''A Magazine'', which covered Asian American issues. Currently, she is serving a four-year term on the board of directors of the Ms. Foundation for Women, a national women's philanthropic organization.
She was also an initial and co-founding member of the Asian Women Leadership Network, now the largest network of professional Asian American women in the country, and was a Founding Sister of both the Asian Women's Center (formerly Asian Pacific American Women's Leadership Network) and the National Asian Pacific American Women's Forum, based in Washington, D.C.
In 2005, Eng co-founded and was the Creative Director of the national policy and communications group, The Opportunity Agenda with fellow co-founders Alan Jenkins, Brian Smedley, and Bill Lann Lee. In 2007 her creative team formed Creative Counsel, which develops projects that connect creative professionals and artists to social justice causes.
Eng's writing has focused on the themes of women's empowerment, and social, racial, and environmental justice. She contributed the foreword to ''Yell-oh Girls!'' (2001), edited by Vickie Nam, and has contributed writings to several books and journals, including: ''The Greatness of Girls'' (2001), "Language is a Place of Struggle" (2008), ''Close to Home: Case Studies of Human Rights Work in the United States'' (2004), ''That Takes Ovaries! Bold Females and Their Brazen Acts'' (2002), ''Closing the Leadership Gap'' (2004) and the ''National Civic Review'' (2009).