Mark A. Nadeau is widely recognized as a leading commentator and has chaired numerous symposia on international dispute resolution. He is a published author, with articles concerning trade competition, product liability and dispute resolution for transfers of technology. Mr. Nadeau has handled cases for foreign clients and domestic clients alike. He is one of seven prominent members of the legal community who published a book and addressed members of the United Nations at the World Summit on Transfers of Technology. Beyond a very active litigation practice in the United States, his international arbitration practice spans Europe, Asia and South America.

Mr. Nadeau is involved in complex commercial litigation throughout the United States and has represented clients in high-profile disputes involving television, aviation, real estate hospitality, trade secret and unfair business practice matters. In conjunction with his product liability work he has appeared in courtrooms in each of the 50 states. He has served as lead counsel in high-profile satellite television multibillion-dollar disputes throughout the United States involving retransmission and antitrust issues. On behalf of several aviation and launch-system clients, he has worked on issues involving rocket technology, joint venture disputes, cockpit avionics, license and patent claims, airworthiness, airframe and engine financing and performance, FBO centers, FAA regulations, environmental issues in aviation and major aircraft overhaul contracts. With an extensive background in all types of real estate disputes, Mr. Nadeau has acted as lead counsel on several multi-party construction and hospitality cases. He has defended many class action suits.

As a result of his considerable work in Southeast Asia and for a large Chinese client in Guangzhou, Mr. Nadeau was invited by the Ministry of Trade and Economic Cooperation for the People’s Republic of China to speak in that country on product liability and international arbitration. The Center for International Legal Studies in Austria has also designated him a fellow of the center. Mr. Nadeau is a member of the London Court of International Arbitration and is active with the World Congress of the International Chamber of Commerce.

At DLA Piper, Mr. Nadeau is the founding partner of the Phoenix office, where he now acts as the co-managing partner and chair of the office's litigation department. He is also a nationally elected member of DLA Piper’s Policy Committee.

Mr. Nadeau also regularly teaches on oral advocacy and trial tactics. He has been recognized by such publications as the American Lawyer for his use of technology in the presentation of courtroom evidence.

The respected research firm Chambers & Partners recognizes Mr. Nadeau in Chambers USA: America's Leading Lawyers for Business, reporting "clients explain that he brings a creative way of thinking and solving problems to matters" and quoting a client who commented "He has a unique ability to read people and situations, and to help clients predict outcomes and assess risk." In 2009, AZ Business magazine listed Mr. Nadeau on its "Top Lawyers List," recognizing him in the categories of bankruptcy, commercial litigation, construction and real estate.