Greg began his finance career on Wall Street in 1977 at Bankers Trust Company. He spent the next 23 years at Bankers in various positions both in London and New York, serving institutional clients in international banking, insurance, commodities, and mortgage finance. In 1999 he left the bank as a managing director in IT following its acquisition by Deutsche Bank, and joined Instinet, a global institutional brokerage firm, in their risk advisory group.

In 2002, Greg founded Sterling Portfolio Management, LLC, an independent RIA, serving individual investors and small businesses, by utilizing institutional asset class funds to construct portfolios based on academic research. In July 2017, Greg merged Sterling into Sax Wealth Advisors, LLC, continuing his investment advisory and financial planning practice as a wealth advisor, particularly focused on retirement and estate planning. 

Greg graduated from Trinity College in Hartford, CT, with a dual bachelor’s degree in philosophy and economics. He also attended New York University Graduate Business School, studying finance before his posting to London in 1978. Married to his wife Toni since 1985, they have raised two daughters and currently reside in Tuxedo, New York, but also spend time in Vermont and Utah, where Toni was born and their eldest daughter presently resides.

His outside interests include skiing, golf, hiking, and reading books. He and his wife also promote live organ donation awareness in support of organ transplantation, based on his wife’s experience as a live liver donor transplant recipient in 2016.

He is a second-generation Irish American whose paternal grandparents arrived in the U.S. in 1911. He knows of at least two instances where his lineal forebears married another Duffy. The first involved his great-great-grandparents, and the second his grandparents, all of whom were born in Monaghan. Having spent his career in finance and investments, Greg appreciates the role luck plays in achieving success and credits his father with always encouraging him to be lucky in life, sage and typical advice coming from an Irish father.