Modeling expanding atmospheres is a difficult task because of the extreme non-LTE situation and the need to account for complex model atoms. Adequate code (PoWR) has been developed successfully in Potsdam, there are two-three other groups worldwide developing codes of comparable complexity. While early work was based on the assumption of a smooth and homogeneous spherical stellar wind, the need to account for clumping became obvious about ten years ago. A relatively simple first-order clumping correction was readily implemented into the model codes. However, it's simplifying assumptions are severe. Only one, uniform density is assumed within each clump, and the clumps are taken to be optically thin at any frequencies. We discuss the consequences of these approximations and the approaches to a more realistic treatment of wind clumping. First results have been obtained from a statistical treatment of optically thick clumps.