During a two-month period 24 of 1,060 (2.3%) samples of respiratory secretions submitted for culture yielded Branhamella catarrhalis in quantities of more than ten colonies per primary plate. Fifteen cultures were "pure" (ie, mixed only with normal throat flora). Of the 16 patients with positive cultures, 14 showed preexisting disease, and 15 had respiratory symptoms. Twelve of 13 patients studied showed more than 10 WBCs/LPF in the direct smear. It is concluded that B catarrhalis should be looked for and reported in such samples, since it seems to be a significant respiratory pathogen.