Mark W. Sullivan, EA

Mark W. Sullivan

Mark is Of Counsel to Schroeder & Associates and leads the highly specialized Tax Controversy group. His practice is concentrated in the areas of Federal tax controversies and litigation support/expert witness services in tax and other white collar cases. He also advises on tax planning and consulting for businesses and individuals. Mark has 25 years of experience in Federal Collection, Examination and Appeals representation.

Prior to starting a private practice in 1998, Mark was an Internal Revenue Officer with the New York, NY, Saint Louis, MO and Washington, D.C. offices of the Internal Revenue Service


  • Enrolled Agent


  • B.A. Sociology & International Relations (1991), Saint Louis University


  • Internal Revenue Service – Collections, Examination and Appeals Divisions (1998)
  • United States District Court for the Eastern District of Missouri – Expert Witness
  • United States District Court for the Southern District of Illinois – Expert Witness
  • United States District Court for the District of Hawaii – Expert Witness
  • Federal Public Defender (E.D. of Missouri) – Consulting Expert