Hydrogen bromide (HBr) is the principal bromine sink species for the ozone loss chemistry induced by bromine-containing gases in the stratosphere. We report a 1994 balloon-based measurement of the daytime stratospheric HBr profile between 20 and 36.5 km altitude. The average concentration result of 1.31¿0.39 parts per trillion in volume (pptv) and an analysis for the concentration versus altitude profile are consistent with previously reported measurements. These results strengthen the evidence for a significantly higher HBr concentration than that predicted by current photochemical models which, on the basis of recent kinetics results, do not include significant HBr production by the reaction branch, BrO+HO2→HBr+O3.¿ 1997 American Geophysical Union