Over the last 10 years, the field of plasmonic research has emerged as an extremely promising technology with several main fields of application: information technologies, energy, high-density data storage, photovoltaics, chemistry, biology, medicine and security. The main focus up to a few years ago was on the ability of plasmonic nanostructures to generate localized regions of highly concentrated electromagnetic fields, however more recently it has also been realized that the electron part of plasmonic excitations can also be exploited in the physical and chemical sciences. Fascinating proof-of-concept applications have over the last three years been demonstrated in areas such as surface-enhanced catalysis (water splitting), photodetectors without bandgaps (Schottky junctions), and nanoscale control over chemical reactions. These applications as well as the most recent breakthroughs and key challenges in this multidisciplinary and dynamic field are the focus of this Faraday Discussion, offering the perspectives of physicists, chemists and ab-initio theoreticians. In this volume the topics covered include: Dynamics of hot electron generation in metallic nanostructures Theory of hot electrons New materials for hot electron generation Applications in catalysis, photochemistry, and photodetection