Ms. Duncan has worked in international advocacy for more than twenty years. In 1992, she founded Diplomatic Resolutions as the world's first private sector embassy, providing expertise in  public sector-private sector development in Latin America, Europe, Asia, the Middle East on behalf of telecommunications, information technology, investment and development organizations. Companies such as Tyco Electronics, Microsoft, Cisco Systems, Lucent Technologies, Oracle, Sun Microsystems, Tandem Computers (now Compaq),UPS and many others worked with Ms. Duncan to create major modernization projects.

The World Bank, the Organization for Economic Cooperation and Development, countries such as Brazil and the Hashemite Kingdom of Jordan and others have called on her skills to develop, implement and support leading edge projects in banking, telecommunications, capital markets, air-traffic control, education and health care.

In June, 2000, Ms. Duncan became President of the Museum of the Americas Foundation. In April, 2001, she debuted the internationally acclaimed www.museamericas.org site during the meeting of all heads of government of the Western Hemisphere at the Summit of the Americas in Quebec.

In early 2002, Ms. Duncan launched the Philharmonic Orchestra of the Americas, and in June, showcased the historic relationship  between the coastal region of South Carolina and the Caribbean in a unique four day exhibition entitled Caribbean Realities, during the famous Spoleto Arts Festival. 

In addition to her work for the Museum of the Americas, she is a noted philanthropist, serving as the President of the Board of Directors of the Washington Symphony Orchestra from 1998 - 2002, on the national Board of Directors of Youth Service America, the International Board of the Council for World Regions (Brussels), the Board of the Pan American Foundation and on numerous international cultural committees.  Ms. Duncan is listed in Who's Who in America and has been recognized for her contributions to the arts and international business development by many organizations.