Until recently, measurements of water vapour in the upper mesosphere were scarce. Instruments on the UARS platform have made the first global measurements of upper mesospheric H2O; the Microwave Limb Sounder is one of these instruments. It has also measured upper mesospheric ozone. So far, various random and systematic errors have prevented accurate retrievals of either species in the upper mesosphere but much can be learned from the raw radiance measurements. In this paper we present these measurements and show how they can provide information on the dynamics of the mesosphere.¿ 1997 American Geophysical Union