Johannes P. Pfeifenberger, principal, Brattle Group. He is an economist with a background in electrical engineering and over twenty-five years of experience in the areas of electricity markets, regulation, and finance. He has assisted clients in the formulation of business and regulatory strategy, submitted expert testimony to the U.S. Congress, courts, arbitration panels, and regulatory agencies around the world, and provided support in mediation, arbitration, settlement, and stakeholder processes.