Results obtained from two experiments concerning the repartition of carbon monoxide in the stratosphere are presented and compared to model predictions. Infrared solar absorption spectra were recorded during a balloon flight from Aire-sur-Adour, France (about 44 ¿N Latitude), in September 1980. The height profile of the mixing ratio presents a minimum of 8¿1 ppb around 22--25 km; it reaches 14¿1 ppb at 35 km. A similar experiment was performed in April--May 1980 from an aircraft (Stratoz II mission) between 64 ¿N and 62 ¿S. The integrated vertical amount above 11.5 km is deduced. There is an important variation of this amount with a maximum (4.45¿1017 mol cm-2) at low altitude and a minimum (0.90¿1017 cm-2) at high latitude related to the height of the tropopause. An asymmetric distribution of CO in the two hemispheres can also be observed.