The response of the stratosphere to 27-day variability in solar activity is studied by using ozone and temperature data obtained from the SCR (Selective Chopper Radiometer) and the BUV (backscattered ultraviolet) experiments on Nimbus 4. In the upper stratosphere (~2 mbar), where solar UV effects are likely to be maximum, the zonally averaged temperature and ozone mixing ratio in the tropics seem to be related to changes in conventional indices of solar activity over several solar rotations. The temperature and ozone are, however, anticorrelated, with temperature varying in phase and ozone out of phase with solar activity. The tropical oscillations appear to be manifestations of oscillations at high latitudes that are very strong during fall-spring epoch of both the hemispheres. The high- and low-latitude oscillations are almost 180¿ out of phase with a transition region at mid-latitudes (30¿--40¿). Their spectral characteristics and phase suggest a complex interaction of dynamical and chemical processes in the upper stratosphere. This conclusion is further strengthened from the inferred changes in ozone sensitivity with respect to temperature, which shows a continuous decrease from the tropics to high latitudes in both the hemispheres.