Juan Carlos Campuzano completed his Ph. D. degree at the University of Wisconsin-Milwaukee in 1978, with a thesis on infrared spectroscopy on metal surfaces under the supervision of Prof. R.G. Greenler. He developed techniques for the study of vibrations at surfaces. From 1978 to 1981, he was a postdoctoral fellow and then a Research Associate at the Donnan Laboratories, University of Liverpool, working with Prof. D.A. King, on photoemission and photoabsorption studies of various solids. Contributions include the development of techniques for mapping Fermi surfaces from photoemission, first observation of an energy gap in ARPES after a phase transition, and the observation of photodesorption. In 1981, he joined the Cavendish Laboratory, University of Cambridge, as Research Associate, working on two-dimensional phase transitions and critical phenomena. Major contributions include the demonstration that in 2D critical phenomena the fluctuations peak above the critical temperature for finite momentum transfer, the experimental observation of hitherto untested scaling laws, and the development of photoelectron spectromicroscopy. In 1985 he joined the Department of Physics at the University of Illinois at Chicago, and in 1987 he also joined the Materials Science Division at Argonne National Laboratory. Research contributions include the experimental observation of conformal invariance at the Ising critical point, the Luttinger scaling of the Fermi volume in high temperature superconductors, the discovery of a new type of singularity in the energy spectrum, momentum distribution sum rules in photoemission, the development of atomic resolution holography, the spectral function interpretation of the photoemission lineshape, the pseudogap in the energy spectrum of underdoped superconductors, new paradigms for Fermi surface changes with unbroken symmetries, the scaling of Fermi arcs, etc.