Mark Guest is an experienced litigator and a partner in Lewis Brisbois’ Chicago office. A member of the firm’s Labor & Employment Practice, he has significant experience representing companies in individual discrimination and wage claims. He also defends companies against the increasing number of claims being brought under the Illinois Biometric Information Privacy Act (BIPA).

Mark also advises clients on laws, regulations, and day-to-day issues related to employer-employee relationship, including but not limited to drafting and revising employee handbooks, employment agreements, separation and severance agreements, as well as contracts with vendors and customers.

Mark recently obtained a $200,000 verdict as first chair at trial on behalf of a client in a contract dispute between two international companies. 

Mark began his career working in legal aid, representing low-income individuals in civil matters. During that time, he gained significant courtroom and trial experience, developing into an attorney who is always ready to identify a reasonable settlement but who is never afraid to go to trial when necessary. Mark is a dynamic litigator who can adjust to changing circumstances and identify unique strategies to obtain positive outcomes for his clients. He is able to advise and guide his clients during difficult circumstances with skill and clarity.

Pro Bono & Philanthropy

  • PADS Lake County Homeless Shelter Board of Directors, 2015-2019

Legal Experience

  • Coach, Loyola University Chicago School of Law’s First Amendment Moot Court Team
    •  Academic Years 2021-2022 and 2022-2023

Professional Presentations

  • Presenter, "Cyber Exposure and Related Claims," National Association of Mutual Insurance Companies (NAMIC), Conference, Orlando, 2022
  • Moderator, "Litigation in a Post-Covid World," Chicago Bar Association Tort Litigation Committee, Symposium, 2021


  • State Bar Admissions
    • Illinois
  • United States District Courts
    • United States District Court for the Central District of Illinois
    • United States District Court for the Northern District of Illinois
    • United States District Court for the Northern District of Indiana


  • Chicago Bar Association
    • Chair of Chicago Bar Association Tort Litigation Committee, 2019-2022


Saint Louis University School of Law

Juris Doctor, May 2009

  • Saint Louis University Law Journal, August 2006-May 2008
    • Notes and Comments Editor, 2007-2008

Saint Louis University School of Public Health

Masters in Public Health, May 2009

University of Notre Dame

Bachelor's Degree, cum laude, May 2005

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