Leveraging Decades Of Combined Experience To Protect Your Interests

Marios Karayannis

Marios Karayannis
  • Founding Attorney


Practice Areas

  • Personal Injury
  • Medical Malpractice
  • General Litigation
  • Divorce


Marios was born in Athens, Greece, on March 11, 1961. In 1965, at the age of 4, Marios came to the United Stats with his parents and brother and became a citizen of the United States in 1978. Marios’ family resided in Naperville where he graduated from Naperville North High School before attending the University of Illinois Urbana-Champaign where he studied Psychology, graduating with a Bachelor of Science in 1983. Marios then attended The John Marshall Law School (now known as University of Illinois Chicago Law School) where he earned his Juris Doctorate in 1986, graduating with distinction as a member of the Law Review and Order of John Marshall.

Marios moved to Elgin, Illinois, in 1988 after marrying his wife, a lifelong Kane County resident. Marios and his wife have resided in St. Charles since 2000 and are fortunate that both of their children also reside nearby in Kane County.

Marios’ legal career began as an intern at the Kane County State’s Attorney’s Office (“KCSAO”) in 1984 while he was still in law school. Upon graduation, he was hired as an Assistant State’s Attorney (“ASA”) with KCSAO where he was quickly promoted to the felony division. In 1990, his last year as an ASA, Mario was named the Kane County Prosecutor of the Year after he tried a record number of cases to verdict. Marios then joined a prestigious Elgin law firm then known as Brady, McQueen, Martin, Collins & Jensen as an associate in 1991 and became a partner in 1996 in the firm, which was then named Brady & Jensen, LLP, where he focused his practice on personal injury, family law, and general litigation matters.

In 2013, and after 22 years with Brady & Jensen, Marios opened his own firm, Karayannis Law Offices, and moved his practice to Geneva. On October 1, 2023, Marios joined forces with his son, Nick, and the two restructured the firm as Karayannis Law Offices, LLC. The firm also physically relocated, and now shares space with another premier Kane County law firm, Griffin, Williams, McMahon & Walsh. LLC.

As he approaches his 40th year in the law, and having tried hundreds of cases to verdict, Marios has unparalleled experience in personal injury, medical malpractice, family law, and general litigation matters. In joining forces with Nick, Karayannis Law Offices, LLC, now offers expertise in workers’ compensation matters along with its historical areas of practice. Marios is energized to continue to serve his clients and feels privileged that he gets to practice law with his son.

Marios is a member of the Kane County Bar Association, the Illinois State Bar Association, the American Bar Association, the Illinois Trial Lawyers Association and has been a member of Lawyers of Distinction since 2019 in personal injury work. He is AV rated by Martindale Hubbell which represents the highest rating a lawyer can achieve via the peer rating system employed by Martindale Hubbell.

Marios has always been an active member of his community serving on the boards of the Community Crisis Center in Elgin and the Friends of Child Advocacy. He and his wife have been members of The Hawk Country Club since 2005 and are parishioners at St. Patrick’s Catholic Church in St. Charles. Marios was a member on the University of Illinois Dad’s Association Board of Directors from 2011 until 2017 and served as President in 2014 and has also served on the University of Illinois Psychology Alumni Board.