The fourth volume of Water Science Reviews presents three fascinating accounts of hydration phenomena in colloidal systems. O.F. Evans and David Miller provide a reappraisal of the role of water in promoting amphiphilic assembly and structure. Donald England’s review of water-soluble polymers highlights those areas that show unique solution properties or where there is contention as to the explanation for the behavior. The final review by Kenneth Newman addresses the hydration of surfaces, a topic of profound scientific and technological importance. Post-graduate researchers interested in topical, critical reviews will benefit from this volume.