Born June 7, 1933, in Lewiston, Maine, Berkelman earned his bachelor's degree in physics from the University of Rochester in 1955 and Ph.D. in physics at Cornell University in 1959. He joined the Cornell faculty in 1961. In the 1960s he worked with then director Robert Wilson and others on groundbreaking measurements of the structure of the proton. Later he led a group of graduate students in the first successful measurement of the size of the pi meson, a charged particle produced when electrons and protons collide.Karl Berkelman was director of the Laboratory of Nuclear Studies from 1985 to 2000, during which time he led the development of the Cornell Electron Storage Ring (CESR) and versions of CLEO, its associated detector. (CESR and CLEO are now part of CLASSE, the Cornell Laboratory for Accelerator-based Sciences and Education.) He led the construction of the CLEO II detector, key features of which have been adopted by other collaborations in the field. During this period the CLEO collaboration led the field of heavy quark and lepton physics.