This report provides information for those involved in concrete design and construction so they are familiar with the factors involved in the effective use of nanomaterials and nanotechnology. This document is not intended as a primary reference source for researchers. Rather@ it is aimed at engineers and architects who wish to gain further understanding of the effects of nanomaterials and nanoadditives being used or proposed for application in concrete. Application of available technology is demonstrated for a range of nanoconcrete structures to show that technological risks are at a known and acceptable level and high industry standards maintained. An overview reports on the main developments in the fields of nanotechnology and nanoscience that are related to concrete@ along with their implications and key findings. Factors affecting performance of fresh and hardened concrete are discussed to enable those involved in the evaluation and formulation of concrete mixtures to determine the effects of these factors. The potential of nanotechnology to improve concrete performance can lead to the development of novel@ sustainable@ advanced cement-based composites with unique mechanical@ thermal@ and electrical properties. New developments have already taken place in nanoengineering and nanomodification of concrete. Current challenges@ including proper dispersion@ compatibility of the nanomaterials in cement@ processing@ manufacturing@ safety@ handling issues@ and cost all need to be solved before the complete potential of nanotechnology can be realized in concrete applications. Additionally@ introduction of these novel materials into the construction practice requires an evaluation and understanding of their potential impact on the environment and human health