The concept of an 'effective' Eddington limit as a lower bound on the syste
m luminosity required for mass loss to be radiation pressure driven is disc
ussed and shown to fall in the interesting regime for high-state non-magnet
ic CV (nMCV). The results of recent hydrodynamical models of radiation-driv
en disk winds (Proga et al. 1998, Proga 1999) are summarised. Mass loss rat
es predicted by these models are then compared with observational constrain
ts. It is shown that either mass accretion rates in high-state nMCV are a f
actor of 2-3 larger than presently supposed or that radiation pressure alon
e is not quite sufficient to drive the observed hypersonic hows. (C) 2000 E
lsevier Science B.V. All rights reserved.