Professor Balaban is one of the leaders in constructive quantum field theory and statistical mechanics. His past work is widely recognized as a tour-de-force in which Professor Balaban has the best solution to the ultraviolet stability problem for both three and four dimensional gauge field models. He is currently attacking still other fundamental problems in quantized gauge fields that govern particle interaction. These include nonlinear models that relate to the current thrust in string theory and unified quantum field theory. Professor Balaban is uniquely qualified for research on these hard problems in mathematical physics.