AETNA Insurance Corp.
All-Control Systems, Inc.
Allstate Insurance, Inc.
American Association of Medical Colleges
American Federation of Teachers
Aramark Corp.
Association of Professors of Medicine
Atlantic Research Corp.
Axiom Real Estate Management Corp
Bank of America
Blank, Rome, Cominsky, & McCauley
Broadview Associates
Bryn Mawr Rehab Hospital
Business Week Magazine
Center for Applied Research
Centric Group
Children's Hospital of Philadelphia
Christie’s, Inc.
Citibank
Clintrials, Inc.
Columbia Energy Group
Comark, Inc.
ConocoPhillips, Inc.
CPR Institute for Dispute Resolution
Delaware Seat Company
DePuy AcroMed, Inc.
DS-Norden Shipping (Denmark)
Elf Atochem North America, Inc. 
Entercom, Inc.
Enterprise Rent-a-Car, Inc.
Evergreen Investments
Fannie Mae
Federal Bureau of Investigation Crisis Negotiating Unit
GE Power Systems (Europe)
General Electric Corporation
Great American Insurance Co.
Harkins Cunningham, LLP
Hewlett-Packard
HSM, Inc. (Brazil)
Janus Capital Management
Johnson & Johnson
Law Enforcement Executive Development Association
Lehigh Valley Hospital
Leonard Davis Institute for Health Care Economics
LOR, Inc.
Main Line Health
Marathon Ashland Petroleum, Inc.
Massey-Knakal Real Estate Services
MCG Corp.
Metlife, Inc.
Merck & Co.
PennCare, Inc.
Pew Charitable Trusts
Pennsylvania Hospital
PPL Energy Plus, Inc.
Prudential Insurance
Smith Barney
Samsung Corporation
Schering Plough, Inc.
Smithsonian Institution
Southeast Anesthesia Associates
Starwood Capital Group
Starwood Hotels
State Street Bank
United Brotherhood of Teamsters
Texas General Counsel Association
Times Mirror Corp.
United Auto Workers of America
United Food and Commercial Workers International Union
University of Pennsylvania Health System
Van Kampen Investments, Inc.
Voith Seimens, Inc.
Welch Allyn, Inc.
World Negotiation Forum (New York)
World Economic Forum (Davos)
Wolseley
Young Presidents Organization