Her research interests include physics beyond the Standard Model, dark matter, and hidden dimensions.

She completed her undergraduate degree in physics and mathematics at Iowa State University in 1982, and earned her doctorate there in 1988.

[4] Hewett began her career as a postdoctoral associate from 1988 to 1991 at the University of Wisconsin-Madison and in 1991–1993 she worked as a physicist at Argonne National Laboratory.

[5] Hewett has served on Program Advisory Committees of SLAC, Fermi National Accelerator Laboratory, Kavli Institute for Theoretical Physics, and the Cornell Electron Storage Ring.

Hewett has worked on the "phenomenology of extra spatial dimensions, extended Higgs sectors, supersymmetry, new physics signatures in heavy flavor physics, dark matter, and the complementarity of experimental probes of dark matter".