Paul Messina is a Distinguished Senior Computer Scientist (part-time) at Argonne National Laboratory, Argonne, Illinois, and a senior advisor on computing to the Director General of CERN, Geneva, Switzerland.  He also serves as principal investigator for the Distributed Terascale Facility and Extensible Terascale Facility projects at the California Institute of Technology (Caltech).

Until April 2002, he held several positions at Caltech: Assistant Vice President for Scientific Computing, Faculty Associate in Scientific Computing, and Director of Caltech's Center for Advanced Computing Research.  During a leave from Caltech from January 1999 to December 2000, he was Director of the Office of Advanced Simulation and Computing for Defense Programs in the National Nuclear Security Administration, Department of Energy.  In that capacity he had responsibility for managing the Accelerated Strategic Computing Initiative, the world’s largest scientific computing program, which is defining the state of the art in that field.  He holds the position of Chief Architect for the National Partnership for Advanced Computational Infrastructure (NPACI), a partnership established by the National Science Foundation and led by the University of California, San Diego.  His recent interests focus on advanced computer architectures, especially their application to large-scale computations in science and engineering. He has also been active in high-speed networks, computer performance evaluation, and Petaflops computing issues. Prior to his assignment in DOE, he led the Computational and Computer Science component of Caltech's research project funded by the Academic Strategic Alliances Program (ASAP) of the Accelerated Strategic Computing Initiative (ASCI).  In the mid 1990s he established and led the Scalable I/O Initiative (SIO), a large scale-effort to address input/output scalability issues in large-scale computing; the SIO had over 15 participating institutions. In the early 1990s he was the Principal Investigator and project manager of the CASA gigabit network testbed. During that period he also conceived, formed, and led the Consortium for Concurrent Supercomputing, whose thirteen members included several Federal agencies, National Laboratories, universities, and industry. That Consortium created and operated the Intel Touchstone Delta System, which was the world’s most powerful scientific computer for two years. He also held a joint appointment at the Jet Propulsion Laboratory as manager of High-Performance Computing and Communications from 1988 to 1998. From 1973 to 1987 he held a variety of positions at Argonne National Laboratory, with the last being Director of the Mathematics and Computer Science Division.