Attorney Sean P. Sullivan has an established track record of dedicated legal practice and skillful advocacy, with a primary focus on Family Law (and related areas such as family businesses) for nearly fifteen (15) years.
Sean’s specialization lies in highly contested matters, whether they pertain to divorce cases, business disputes, or contested probate matters. He is a genuine attorney and counselor at law, guiding clients with skill and compassion during their most challenging times. While he possesses an unwavering ability to take any matter to trial, Sean acknowledges the significance of skillful negotiation in reaching optimal resolutions. He maintains open and direct communication with his clients, ensuring they comprehend the issues at hand and the potential outcomes they might face. Sean believes in presenting all possible scenarios, including the toughest realities, and collaborates diligently with his clients to advocate for the best possible results.
Sean’s clients and peers alike recognize him for his fair and practical approach, his zealous advocacy, and his competence in the courtroom. Fully aware of the profound impact contested litigation can have on his clients’ lives, he dedicates his utmost care and attention to every case.
As a mediator, Sean shrugs off his litigator role and rolls up his sleeves to help couples and co-parents attain private, timely resolutions to sensitive family matters. In this work, Sean’s non-judgmental attitude and many years of experience in local family law courtrooms are incredible assets to the families who he assists. Some of his most gratifying achievements stem from helping parties reach reasonable agreements, avoiding the time and resources that accompany protracted litigation. Sean’s mediation credentials hail from the esteemed Northwestern University mediation program, where Sean studied under some of the best before successfully completing Northwestern’s mediation certification program.
Sean attended and received his J.D. from Western Michigan Law School. Sean also holds a Bachelor of Arts degree in Psychology from the University of Iowa. Sean often leans into his psychology background when devising legal strategies and in his approach to negotiations.
A lifelong resident of DuPage County, Sean attended Naperville North High School and returned to the area after college and law school. These days he is proud to serve DuPage County as an active member of the Board of Directors for DuPage County Court Appointed Special Advocates (DuPage County CASA), witnessing firsthand the invaluable service this organization provides to children in the DuPage County legal system who have limited advocates. Sean also gives back by frequently serving as a court-appointed guardian ad litem (GAL) and mediator in the DuPage County court system.
Sean is vice chair of the DuPage County Bar Association Family Law section and a past chair of the DuPage County Bar Association section on Professional Responsibility. Sean is also an active member of the Illinois State Bar Association Child Law Section counsel, where he is actively involved in the GAL Best Practices Subcommittee that is assisting the Illinois Supreme Court with standardizing additional court forms dealing with GAL appointments and best practices. Sean is the recipient of several professional awards, most notably: being named a SuperLawyer in 2024 in the area of Family Law. Each year, no more than five percent of the lawyers in the state are selected by the research team at Super Lawyers to receive this honor. Super Lawyers, part of Thomson Reuters, is a rating service of outstanding lawyers from more than 70 practice areas who have attained a high degree of peer recognition and professional achievement.
When not immersed in legal research or trial preparations, Sean indulges in his passions for cooking, golfing, and enthusiastically cheering on his beloved Cubbies in their pursuit of another World Series title. Sean and his wife are also dedicated animal rescuers and have had the joy of adopting their pet dogs from local shelters over the years. Currently, their puppy Roxy is keeping them on their toes with her boundless energy and quirky personality. In addition to their personal pursuits, Sean and his wife actively support the Cystic Fibrosis Foundation, zealously contributing to finding a cure for this devastating disease that profoundly affects their extended family.
Attorney