Space Sciences Laboratory, U. C. Berkeley, Berkeley, CA 94720-7450

HESSI will perform spectroscopy from roughly 3 keV to 17 MeV, well over three orders of magnitude in energy, with a single set of 9 cryogenically cooled germanium detectors. I will describe the HESSI spectrometer, discuss the procedures for spectroscopic data analysis, and show the estimated sensitivity of HESSI to important features of flare spectra.