Tailings are produced from the processing of mineral ores and are commonly stored within embankment dams. The design of the dams requires application of sound engineering principles and an understanding of the properties of the tailings. This Bulletin provides a framework for classifying different types of tailings, ranging from ultra-fine to coarse, based on their geotechnical properties and provides typical geotechnical parameters for the different tailings types. Technologies for dewatering tailings to reduce the risk of storage continue to be developed and the different technologies, from thickening to filtration, and re-application of old technologies are presented to illustrate the options available and, where appropriate, typical in situ properties. This bulletin is directed towards a wide audience of stakeholders: designers, owners, regulators, communities and various organizations and provides a reference for communicating tailings properties and the benefits and limitations of technologies. All mining operations, and thereby tailings operations, are unique. There is no one-solution-fits-all. Tailings dam designs need to account for site-specific conditions, such as climate, physiography, geochemistry, geomorphology, seismology, mining processes, environment, and community setting, with the application of technologies playing an important role in developing safe, sustainable tailings facilities.