Geometry effects in the sol and divertor

Geometry effects in the SOL and divertor, which are the main focus of a var iety of present tokamaks, are reviewed. Since divertor detachment constitut es a central element in this context, some basic results on divertor detach ment are also summarised. The discussion of issues that played a role in re cent experimental campaigns and their theoretical and numerical analysis fo rm a major part of the paper. Emphasis is placed on gas target related effe cts. An attempt is made to reduce the impact of geometry to a small number of basic mechanisms.