The contribution of fundamental frequency (F0) to the distinction between lenis and fortis plosives is investigated for German in monotone, falling, and rising pitch patterns. A larger F0 drop is found in the stressed vowel before lenis, as against fortis, in disyllabic words with the contour high + fall. These F0 differences do not have aerodynamic causes due to articulatory constraints on phonation but can be related to an active laryngeal control in two production patterns differing in overall articulatory effort and also resulting in an articulatory timing contrast. Hypotheses are formulated as regards the importance of this F0 difference for perception, and with respect to the production and the perception of the lenis/fortis opposition along the F0 parameter in English.