Volume 3 of Annual Surfactants Review focuses on the diversity of surfactants, both in terms of chemical structure and physico-chemical / surface active properties. These properties may be predictable for simple molecules, but for most commercial surfactants (which may be regarded as multi-component blends) this is not so easy. In the first chapter of this volume, detailed consideration is given to surfactant applications in the context of structure-performance relationships. The end uses of surface active agents are classified by industrial sector and the surfactant properties required for each application are presented in detail. The result is a unique guide to the influence of chemical structure on performance in end use. Many applications of surfactants feature formulations which incorporate polymeric materials. The topic of surfactant-polymer interactions is receiving considerable attention at present and so a chapter has been included on this area. In an attempt to illustrate the diversity of surfactant uses and focus on some of the latest developments in application technology, five areas of application are presented: natural surfactants for drug delivery systems, surfactants used in the construction industry, preparation and end uses of inverse emulsions (for example, as flocculants), the use of surfactants in plastics flotation (part of the plastics recycling process) and the role of surfactants in 'dynamic wetting'.