Analysis and Characterisation of Metal-Based Nanomaterials, Volume 93 in the Comprehensive Analytical Chemistry series, introduces recent developments in analytical methodologies for detection, characterization and quantification of metal-based nanomaterials and their applications to a variety of complex environmental, biological and food samples as well as different consumer products. Single-particle inductively coupled plasma mass spectrometry is highlighted as a powerful analytical tool for number-based concentration and size distribution, also from the metrological viewpoint. An emerging approach for the measurement of multi-metal nanoparticles by single-particle inductively coupled plasma time-of-flight mass spectrometry is discussed. Imaging of metal-based nanoparticles by hyphenated inductively coupled plasma-based techniques is also introduced. The potential of different liquid chromatography and field flow fractionation separation techniques hyphenated to inductively coupled plasma mass spectrometry is emphasized as a powerful tool in particular for complex matrices and small particles sizes. The use of different microscopic techniques for the characterization of metal-based nanoparticles and characterization of metal-based nanoparticles as contrast agents for magnetic resonance imaging are presented. Moreover, occurrence, behaviour and fate of inorganic nanoparticles in the environment is overviewed. Finally, the need for quality control standards and reference nano-materials is emphasized throughout.