This book provides a comprehensive approach to deal with agro waste products that affect dramatically the environment in countries that produce palm oil. The use of Palm Oil Fuel Ash (POFA) as a supplementary cementing material(SCM) not only works as a genuine idea to get rid of this environmental burden but also open the way to generate revenue for this industry. A complete study to investigate the effects of POFA on durability of high strength concrete was carried out and the presented findings suggest that POFA can be effectively used as SCM and there is a potential for marketing it worldwide. It is forecast that using SCM like POFA in concrete will have an impact on the environment by reducing the amount of cement used in construction industry.