Sandi Hallmark

Sandi Hallmark

Hallmark Advisory Group


Sandi Hallmark is an attorney with over thirty years of proven expertise in corporate and financial transactions, specializing in joint ventures, strategic alliances, structured financial transactions and mergers and acquisitions, with extensive knowledge of partnership tax law. As the founder of the Hallmark Advisory Group, Ms. Hallmark provides strategic counsel for US and international public and private companies and financial institutions.

Ms. Hallmark has been an active member of the Washington business and philanthropic communities for three decades.  She is an NACD Governance Fellow and currently serves on the boards of Careers through Culinary Arts Program (C-CAP), the District of Columbia Access to Justice Foundation and Center for International Sports Leadership, Inc., as well as Leadership Greater Washington. Committed to the development of the Washington community, as well as the betterment of society throughout the world, Ms. Hallmark has provided extensive pro bono assistance to a number of organizations, including Washington 2024, in support of the Washington DC bid for the 2024 Olympics, Center For International Sports Leadership, Inc., in support of efforts to bring international sporting events to the Washington region, and the International Senior Lawyers Project and the Commercial Law Development Program, a division of the US Department of Commerce, and Civilians in Conflict, in support of sustainable economic development and the rule of law.

Prior to founding the Hallmark Advisory Group, Ms. Hallmark was a partner at Akin Gump Strauss Hauer & Feld LLP and King & Spalding LLP, both in Washington. She began her legal career at the Internal Revenue Service, Office of the Chief Counsel. Ms. Hallmark has a B.A. from Brandeis University, a J.D. from Cardozo School of Law and an LL.M. from Georgetown University. She lives in Mclean with her husband, Robert Hallmark, and their two sons.