John K. Lyons represents major US and international corporations, committees, lenders and boards of directors in complex business reorganizations, acquisitions and divestitures, typically in distressed situations.

John has served as counsel in many significant business reorganizations, including as counsel for the official committee of unsecured creditors of American Airlines and its affiliates in their chapter 11 reorganization, including representation of the committee in connection with fleet restructuring efforts with aircraft suppliers, financiers and lessors. This transaction was recognized in the Corporate & Commercial category in the Financial Times' 2013 US ''Innovative Lawyers'' report. He also has represented companies in other high-profile chapter 11 cases, including VeraSun Energy Corporation, one of the largest ethanol producers in the US; Delphi Corporation, a leading global technology innovator and Tier 1 supplier to nearly every major automotive original equipment manufacturer; Interstate Bakeries Corporation, one of the largest wholesale bakers and distributors of fresh baked bread and sweet goods in the US; Exodus Communications, Inc., the world's largest Internet data center provider, in the sale of its international business to an affiliate of Cable & Wireless plc for US$575 million through a fast-track chapter 11 process; US Airways, Inc., one of the nation's largest airlines, in the successful restructuring of its business in the wake of the events of September 11 and the economic downturn in the airline industry; Favorite Brands International, Inc., a manufacturer of candies and confectioneries, in connection with its successful restructuring and consequent sale of its business; Einstein/Noah Bagel Corp., a national bagel restaurateur with more than 400 stores; and Montgomery Ward, LLC in connection with the nation's largest retail liquidation, which generated proceeds in excess of US$1 billion; Air Transport International, LLC in connection with its sale to BAX Global through chapter 11; and the Special Committee of Triangle Petroleum Corporation in connection with the chapter 11 cases of its subsidiaries. 

John also represents a number of private equity and distressed investors, including Black Diamond Capital Management, LLC as a majority term lender in connection with the Boomerang Tube chapter 11 restructuring; Goldman Sachs in a number of matters; Avalon Capital Group, Inc. in connection with litigation and consensual resolution of its investment exit from Rainbow Production Services; Health Evolution Partners, as a sponsor and secured lender, in the wind down of one of its portfolio companies; Verizon Capital Corporation in the restructuring of two investments in power facilities in Massachusetts and Mississippi; Calliope Capital Corporation and affiliate lenders in connection with the chapter 11 case filed by PPM Technologies and subsequent credit bid purchase of PPM's business; and CenterPoint Properties in connection with an investment. 

John also represented several clients in connection with fraud investigations and asset recovery efforts, including Jonathan D. King, Chapter 7 Trustee in the Zetta Jet Pte., Ltd. and Zetta Jet USA, Inc. bankruptcy cases, the special committee of the board of directors of PRC-based ShengdaTech, Inc. to complete the committee's investigation of ShengdaTech and to safeguard assets through chapter 11 and foreign proceedings; Paliafito America, Inc. in connection with the successful collection of millions of dollars of assets from international debtors and principals through prejudgment seizure of assets and prosecution of preference actions; and a large commodity supplier in connection with the tracing and civil seizure of millions of assets from a top executive that embezzled money. 

John also has represented clients with respect to a wide array of out-of-court and cross-border transactions in distressed situations, including the representation of club lenders Rabobank NA, Standard Chartered Bank and DBS Bank in the Pacific Andes/China Fishery chapter 11 cross border restructuring; Silver Airways in connection with the sale of its business; a global microfinance company and its Central Asian subsidiary in connection with restructuring efforts; Express Group Holding in its wind down efforts; Forge Group Inc. in its sale to South Africa based DRA Global; Australia owned Marion Energy, Inc. in its US restructuring efforts; Bankruptcy Management Solutions, Inc. in its successful out of court restructuring and subsequent sale of its business to Stone Point Partners; and Faurecia N.A., a French automotive conglomerate, in the purchase of AP Automotive, Inc., a large American automotive parts supplier.

In 2019, John was appointed to the State Universities Retirement System Board of Trustees (SURS). SURS administers retirement plans for employees and retirees that work or have worked in the Illinois higher education system, including the state universities and community colleges, serving more than 232,000 beneficiaries and managing over US$19 billion in assets.