W. Patrick Sullivan

Robert J. Misey, Jr. is a top attorney recognized by Best Lawyers in the practice area(s) of Tax Law. Robert J., who practices law in Milwaukee, Wisconsin, has been recognized since 2009. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Robert J. is held by other top lawyers in the same geographic and legal practice area.

Nathan K. Johnson is a top attorney recognized by Best Lawyers in the practice area(s) of Litigation - Trusts and Estates, Nonprofit / Charities Law, Tax Law and Trusts and Estates. Nathan K., who practices law in Waukesha, Wisconsin, has been recognized since 2019. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Nathan K. is held by other top lawyers in the same geographic and legal practice area.

Frank Pitsoulakis is a top attorney recognized by Best Lawyers in the practice area(s) of Real Estate Law. Frank, who practices law in Milwaukee, Wisconsin, has been recognized since 2022. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Frank is held by other top lawyers in the same geographic and legal practice area.

Tom Kammerait is a Shareholder and the Chair of the Business Succession Planning Section. Tom represents businesses on all aspects of their corporate and business needs including transactional matters, tax, general corporate, real estate, technology, and estate planning issues. Tom generates value by helping clients set priorities for enhancing the value of their businesses and identifying risk management strategies, on a tax-efficient basis. He is also a CPA, so his knowledge of accounting g...

Aaron H. Aizenberg is a top attorney recognized by Best Lawyers in the practice area(s) of Commercial Litigation. Aaron H., who practices law in Milwaukee, Wisconsin, has been recognized since 2020. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Aaron H. is held by other top lawyers in the same geographic and legal practice area.

Joe is the chair of the firm’s Litigation Practice Group. He manages a variety of complex cases involving software class actions, real estate, products liability, banking, intellectual property, and anti-trust matters. He has extensive experience representing both large and small plaintiffs and defendants in challenging civil litigation. He has been selected as a member of the Wisconsin Super Lawyers for six years in a row. Prior to joining O’Neil Cannon, Joe was an associate at t...

Ashley is a shareholder focusing on civil defense litigation, handling matters at all stages - from pre-suit stage investigations and negotiations, through discovery, settlement, trial, and appeal. She has successfully defended individuals, professionals, corporations, employers, and insurers in matters involving allegations of personal injury, premises liability, product liability, and insurance coverage. Ashley is committed to providing service that produces successful results and her clien...

Andrew Christman is a Shareholder in the Litigation and Risk Management Practice Group at von Briesen & Roper, s.c. He has extensive litigation experience involving matters in numerous state and federal courts across the country. He focuses his practice on toxic tort, product liability, premises liability, and insurance litigation. Andrew also has experience in construction litigation, professional liability, and appellate litigation. Andrew helps clients develop, maintain and implement d...

Joe Camilli is a Shareholder in the Business Practice Group at von Briesen & Roper, s.c. He focuses his practice on business and corporate issues, mergers and acquisitions, and employment matters. Joe enjoys working with entrepreneurs, start-ups, and small businesses. Joe finds the greatest success and joy in helping clients navigate and conquer the challenges and opportunities they face. Whether clients need help selling their business, navigating a challenging employment situation, or r...

Background Mr. Prachthauser was born in Milwaukee, Wisconsin, on January 7, 1951. Prior to joining the firm, he was House Counsel for Employers Insurance of Wausau. He is married to Joan Marie, and they reside in Hartland, Wisconsin. He has two daughters, Emily and Tracy. Lectures Mr. Prachthauser is a frequent presenter and speaker for the State Bar of Wisconsin, American Board of Trial Advocates, and Wisconsin Academy of Trial Lawyers. He has been a Civil Trial Practice Instructor at the Un...