The tropical tropopause region (TTR) represents the transition zone between the uppermost troposphere, which can be directly influenced by the presence of deep convection, and the lower stratosphere, which convection may influence indirectly by dynamical and radiative effects. The TTR is known to be forced on interannual time scales by the stratospheric QBO and by shifts in convection due to sea surface temperature fluctuations associated with ENSO. Other, more subtle effects include solar forcing and changes in the residual circulation due to interannual variations in extratropical wave driving. We examine the effect of ENSO in some detail through the use of radiosonde and NCEP reanalysis data. When SST is anomalously high in the central tropical Pacific, tropopause height (pressure) is high (low) throughout the tropics, with largest perturbation amplitudes in the subtropical Pacific. At the same time the tropopause is cold over the tropical and subtropical Pacific sector but warm elsewhere. Over the extratropics, wavelike perturbations in the tropopause are seen, with a low tropopause corresponding to regions of higher tropopause temperature and pressure, and vice-versa. Temperature anomalies in the lower stratosphere tend to match those at the tropopause over much of the globe, with opposite anomalies in the upper troposphere. The vertical structure of these perturbations is consistent with the expected potential vorticity anomalies induced by quasi-stationary Rossby waves and vertically propagating gravity waves forced by displacements of tropical convection. Similar relationships are associated with the propagation of tropical convection due to the Madden-Julian Oscillation and higher frequency equatorial waves coupled to convection on intraseasonal time scales. The vertical structure of these perturbations is consistent with the forcing of vertically propagating Kelvin waves by the moving convective heat sources associated with these disturbances.