Wolf-Rayet stars have the strongest persistent winds among hot stars. This has the advantage that one can easily observe their wind structure globally using Doppler spectroscopy of their strong emission lines (to be superceded soon by ultra-high resolution interferometric imaging!) ... but the disadvantage that the winds are opaque close to the star. Superposed on a general outward cooling trend, all WR winds appear to exhibit small-scale temporal fluctuations in their emission lines. The interpretation is that we are probably seeing the manifestation of some kind of turbulent shocking superposed on the general outflow, with little or no background, smooth component. The emission from the emission subpeaks appears to follow $\sim$ the same ionisation trend with radius as the global line emission. Evidence is mounting that WR winds are not alone: other hot-star winds may also show similar (appropriately scaled) clumping effects. Consequences of wind clumping are numerous (e.g. revision downwards of mass-loss rates, triggering dust formation,....).

A minority of WR stars also reveal large-scale, quasi-periodic line variations, reminiscent of DAC/CIR behaviour in O-star winds.