  Small-scale inhomogeneities, or `clumping', in the winds of hot, massive
stars are conventionally included in spectral analyses by assuming optically
thin clumps. To reconcile investigations of different diagnostics using this
microclumping technique, very low mass-loss rates must be invoked for O stars.
Recently it has been suggested that by using the microclumping approximation
one may actually drastically underestimate the mass-loss rates. Here we
demonstrate this, present a new, improved description of clumpy winds, and show
how corresponding models, in a combined UV and optical analysis, can alleviate
discrepancies between previously derived rates and those predicted by the
line-driven wind theory. Furthermore, we show that the structures obtained in
time-dependent, radiation-hydrodynamic simulations of the intrinsic line-driven
instability of such winds, which are the basis to our current understanding of
clumping, in their present-day form seem unable to provide a fully
self-consistent, simultaneous fit to both UV and optical lines. The reasons for
this are discussed.
