About Diane

Diane Giordano is a partner in the Tax & Business Services division in the Firm’s Melville, New York office. She works closely with large, multi-state companies as well as family-owned businesses, providing tax and tax credit consulting, financial statement disclosure, and compliance services. Diane’s clients also include U.S. Securities and Exchange Commission (SEC) reporting entities for which she provides various tax provision and consulting services.

Diane frequently speaks to professional and industry organizations on a variety of tax topics and authors numerous articles that have been published in various professional publications. She’s previously served as the editor of the Firm’s tax newsletter and the annual Marcum Year-End Tax Guide.

Diane is also a leader in the Firm-wide integration process and is a frequent instructor on various tax technical topics, including tax credits and net operating losses.

Prior to joining Marcum in 2005, she worked at other global and large accounting organizations.

Professional & Civic Affiliations

  • American Institute of Certified Public Accountants (AICPA)
  • New York State Society of Certified Public Accountants (NYSSCPA), Nassau Chapter, Past Board Member
  • Moxxie Network
  • Half Hollow Hills Business Partnership
  • Long Island Alzheimer Foundation, Past Committee Member
  • Mentoring Partnership of Long Island, Past Advisory Board Member
  • Girls, Inc. of Long Island, Past Board Member
  • American Heart Association, LI Chapter, Past Board Member

Articles & Presentations

  • Long Island Food Council Growth of the Urban Foodscape Panel, 2023
  • Total Food Service Virtual Breakfast Event Panel, 2023
  • Restaurant Revitalization Fund Webinar, 2021
  • ASCM Long Island Forum, 2020
  • Life After Coronavirus Webinar, 2020
  • Year-End Tax Update, NYSSCPA Nassau Chapter, 2009-2014


Industry Focus

Food & Beverage
Closely-Held Businesses
SEC Reporting Entities


Certified Financial Planner
College for Financial Planning

Master of Science, Taxation
C.W. Post Campus Long Island University

Bachelor of Science, Accounting
Hofstra University

Awards & Recognition

Premier Business Women of Long Island, Richner Communications, 2023
Long Island Power Women In Business, Schneps Media, 2021, 2015
Notable Women in Accounting, CRAINS New York, 2020
Ones to Watch in Accounting, Long Island Business News, 2020
Top 50 Most Influential Women in Business, Long Island Business News, 2013 & 2011