The volume addresses, in addition to legal aspects in Germany and the EU, primarily technical innovations in the field of groundwater protection and remediation. For instance, it presents biosparging as a method for in-situ remediation of mineral oil contamination, as well as the turbo well for the remediation of volatile contaminants. Other contributions discuss the applications and limitations of numerical groundwater models in hydrogeological practice, describe the possibilities of groundwater exploration using satellites, and engage with issues of quality assurance.