: The extensive mining production worldwide results in vast amounts of residues requiring the construction of new tailings dams. As site availability is limited due to environmental restrictions, tailings dams tend to be very large and, with heights of over 200 m in some cases, often raising stability concerns. Past experience has shown that failure of tailings dams during earthquakes can be catastrophic, with detrimental consequences for the neighbouring communities, environment and the economy. Prominent examples of such cases are the failure of the El Cobre N°1 dam in Chile, due to the 1965 earthquake, and more recently the Fundão tailings dam failure in Brazil in November 2015. This article investigates the monotonic and cyclic behaviour of tailings sands for different fines content and at a range of relative densities and confining pressures. Several aspects of the behaviour of tailings sands, such as compressibility, strength characteristics and cyclic response, are compared with those of natural sands. Based on the available laboratory test results and the interpretation performed, it is possible to distinguish certain features of this type of material, which are not typically observed in natural soil deposits, and to address common misleading comparisons between the behaviour of natural and tailings sands.