Construction and demolition waste constitutes a major portion of total waste production in the world, and most of it is used in landfills. The re-use of concrete rubble collected from demolished structures is an important issue. After crushing and screening, there is the possibility of appropriately treating and reusing such waste as aggregate in new concrete, especially in lower level applications. Different aspects of the topic beginning with a brief review of the European initiatives and definition in terms of C&D waste generated and recycled aggregates produced from C&D waste are given. Along with a brief overview of C&D waste, a summary of the situation in Luxembourg in use of recycled aggregate is discussed. This writing concludes by identifying some of the major barriers in more use of recycled aggregate concrete, including lack of awareness, lack of knowledge, barriers of specifications/codes for reusing these aggregates in new concrete.