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Electron spin resonance (ESR) dating can date many materials, including hydroxyapatite in enamel and some fish scales, aragonite and calcite in corals, molluscs, some travertine and calcrete, and quartz from ash, fluvial deposits, and some flint. Dating studies using these materials have numerous potential applications in many varied Quaternary settings. ESR dating uses signals resulting from trapped charges created by radiation in crystalline solids. Ages are calculated by comparing the accumulated radiation dose in the dating sample with the internal and external radiation dose rates produced by natural radiation in and around the sample and produced by cosmic radiation. When compared to other dating techniques, age agreement has been excellent for teeth, corals, molluscs, and quartz. Recent improvements have included using a more complex modelling technique to calculate the cosmic dose rates and more detailed modelling techniques for dealing with variable external dose rates. Methods in development include using quartz from buried fluvial valleys to date geomorphic surfaces and using the signals in barnacles and benthic foraminifera for dating fossils or their associated sediment. New chronometer applications recently developed include using coral and mollusc dates to build sealevel curves and to monitor volcanic activity and tectonic uplift, using tooth and mollusc dates to assess water availability in deserts, and using isochron data to assess U uptake processes into teeth. When coupled with other geochemical and geomorphological techniques, ESR can provide the chronometric control to build paleoclimatic and other paleoenvironmental records. Many other applications are possible, from heating studies for artefacts to dating sulphates and other minerals on distant planets. (C) 2016 Elsevier B.V. All rights reserved.