Dr. Arthur H. Lefebvre (1923-2003) was Emeritus Professor at Cranfield University and Purdue University.During his career he developed several innovative atomizers, including prefilming (in the 1960s) and effervescent (in the 1990s) designs for aircraft engines. Improvements in atomization greatly reduced the emissions of soot (particulate combustion product) and were instrumental in increasing the reliability of the combustor that was critical to improve the engine robustness. Lefebvre was a leading pioneer in the development of the jet engine, along with Sir Frank Whittle and Hans von Ohain. He shared his expertise with an annual week-long gas turbine combustion short course from 1962 to 2003. Dr. Dilip R. Ballal (1946-2012) was the Hans von Ohain Distinguished Chair Professor at the University of Dayton, and Director of the von Ohain Fuels & Combustion Center. Dr. Ballal was a Life-Fellow of both ASME and AIAA, and editor of the ASME Journal of Engineering for Gas Turbines and Power. Among other honors, Dr. Ballal was recipient of the Tom Sawyer Award for his achievements in the turbine combustion field. Dr. Scott Samuelsen is Professor Emeritus, Mechanical and Aerospace Engineering, at the University of California, Irvine, and Director of the National Fuel Cell Research Center. He received his Ph.D. in 1970 from the University of California, Berkeley. Dr. Samuelsen's interests include energy conversion, fuel cells, combustion, fuel sprays, laser diagnostics, air quality, turbulent transport, alternative fuels, the modeling of reacting flows, practical energy systems, and the conflict between energy and the environment. His current research activity focuses on energy generation, distribution and utilization, and includes the production of electricity, motive power and propulsive power from both fuel cells, gas turbines and hybrids of both. His work also explores the environmental impact of these energy systems, the dynamic between energy generation and atmospheric quality, and the development of environmentally preferred, high-efficiency energy generation integrated into buildings and building complexes. Dr. Samuelsen directs the Advanced Power and Energy Program (APEP), which encompasses the National Fuel Cell Research Center (NFCRC), the UCI Combustion Lab (UCICL) and the Pacific Consortium on Energy and the Environment (PARCON). His work at the UCICL is directed toward the development of advanced stationary gas turbine power systems. Research at the NFCRC is leading the evolution of power generation fuel cells, and the PARCON accelerates the development and deployment of advance energy systems around the world.