Nam Ngum 2 dam, a large concrete face rockfill dam (CFRD) of 182 m height, is under construction and impounding is scheduled to start at beginning of April 2010. The dam is situated in a narrow valley and founded on sedimentary rock of variable strength. Dam design principles comprising dam zoning, face slab design and instrumentation are outlined. Foundation treatment including grouting and measures below the plinth are presented. The properties of the available rockfill materials and their influence on the dam zoning are discussed. Emphasis is given to the rockfill properties and placement procedures which influence dam behaviour during construction, impounding and operation.