Shepherd, in prep.[]{data-label="fig:s140co"}](s140ovro_bw.ps){width="10cm"}

As well as molecular outflows, the massive YSOs also have compact, ionized winds. These manifest themselves through thermal radio spectrum with a spectral index close to +0.6 expected for a constant velocity wind (Wright & Barlow 1975). They also give rise to broad, single-peaked H I emission lines in the IR (Bunn et al. 1995). These typically have FWHM of about 100  and FWZI up to several hundred  which is a lower limit on the wind’s terminal velocity. NLTE modelling shows that there is a common origin for the radio continuum and IR line emission (e.g. Höflich & Wehrse 1987). The typical mass-loss rates estimated for these ionized winds are of order $\sim$10$^{-6}$.

Clues to what is driving the ionized winds comes from resolving their spatial structure. Here the picture is also mixed as it is for the molecular outflows (see review by Hoare 2002). In some cases radio jets are seen as in their low-mass counterparts. By far the most spectacular example is the 2.6 pc long wiggling jet seen in the GGD27 system (Martí et al. 1993). This powers radio and optical Herbig-Haro objects at its termination and looks just like a scaled up low-mass 