About Daniel J.
Daniel J. Kollias earned his bachelor’s degree in economics from the University of Michigan in 1995 and completed his law degree at Notre Dame Law School in 1999. Those years shaped his approach to practice: methodical and courtroom-ready. He moved quickly from law school into public service, joining the Cook County State’s Attorney’s Office as a prosecutor the same year he finished law school.
After several years in the prosecutor’s office, Kollias shifted into private practice. He opened the Law Offices of Daniel J. Kollias, P.C. in 2003 and built a solo practice that handled litigation and client representation in local courts. In 2009 he joined Mullen, Winthers & Kollias as a partner. Five years later he helped form Kollias & Giese, P.C., continuing in a partner role. In 2020 he became owner and managing lawyer of Kollias, P.C., the current iteration of his firm.
Kollias is admitted to practice in Illinois and in the United States District Court for the Northern District of Illinois. He holds a Guardian ad Litem certification from the DuPage County Bar Association and remains an active member of that association. His background combines trial experience from public prosecution with years of civil practice in private settings. That blend informs how he prepares cases and advises clients in court matters.
Today he leads Kollias, P.C. and oversees client matters in state and federal courts in Illinois. He manages case strategy, handles courtroom work, and carries responsibility for the firm’s operations. He continues to serve as a Guardian ad Litem when appointed and maintains an active role in the DuPage County Bar Association. He currently concentrates his practice on litigation and courtroom representation in Illinois state and federal courts.
