Performance of cement based materials is a major concern and new ways to improve the engineering properties of these cementitious materials to ensure longevity are being investigated. Use of nanotechnology is one such novel route through which high performance materials can be developed. Nanotechnology can be gainfully applied in cementitious materials to address the issues of durability and sustainability. Manipulation at the nanoscale can change chemical reactions, temperature, electricity, magnetism etc. In addition, the nanomodification can result improvements in strength, shrinkage, ductility and impact resistance. Nano chemistry offers the possibilities of understanding the extremely small complex structures of cement based materials at nano level. It is expected that, when nano particles are incorporated into conventional building materials, such material can possess advanced or smart properties required for the construction of high–rise, long-span or intelligent civil and infra systems.