The aim of this book is to provide comprehensive information of recent progresses in development of functional nanomaterials and nanocomposites which are used for environmental remediation of a variety of contaminants. It deals with the different aspects of nanotechnology in water, air and soil contamination. In addition, a detailed approach towards the different remediation procedures by various nanomaterials like metal nanoparticles, polymeric nanoparticles, carbon nanotubes, dendrimers etc. is included.