Mine wastes disposal facilities are exposed to natural conditions that influence their geo-environmental behavior.   Unsaturated conditions commonly prevail in waste rock piles, while tailings in impoundment experience changing water content and pore water pressure following hydraulic deposition cycles.   These aspects must be considered in the analysis and design of such facilities, early at the planning stage, to optimise wastes management during mining operation and for reclamation upon closure. This invited presentation will give an overview of some of the main unsaturated properties of tailings and waste rocks from hard rock mines. This will include a review of specific testing procedures and typical results related to the water retention curve and unsaturated hydraulic conductivity function.  Experimental results obtained on tailings subjected to drying and desiccation, the impact of suction on their compressibility, and unsaturated geotechnical parameters such as tensile strength, apparent cohesion, and deformation modulus will also be shown.  The presentation will then illustrate how these properties affect in situ response, with a focus on the hydro-geotechnical behavior and stability of  piles and impoundments.  The impact of unsaturated conditions on reclamation methods, including mono- and multi-layered cover systems, will also be addressed.  A few additional issues will be considered such as  densified (dewatered) reactive tailings, cemented paste backfill (made with tailings) in mine stopes, control of water contamination from reactive (sulphidic) mine wastes, and monitor techniques.