"Concrete has not been a competitive alternative for roof applications due to the heavy weight and construction complexity of concrete components, which results in being less cost effective than steel. Despite the advantages of structural steel roof systems, they have the following disadvantages: low fire resistance, being prone to corrosion, high maintenance cost, long lag period in steel orders, and increasing prices of steel. Most of these disadvantages can be addressed by using precast concrete components as they have excellent fire and corrosion resistance, low production and maintenance cost, and short order period. Recently more extensive use of precast/prestressed concrete components, which are fabricated off-site and then connected on-site, has been taking place worldwide since it shows significant benefits compared to the conventional poured on site concrete technology. Among others, the benefits are in accelerating the construction time, enhancing the quality of concrete works, improving its durability and in general generating competitive structural cost. Pre-grouted prestressing tendon, primarily in the form of single strands, was generally applied to transverse prestressing of deck slabs or other work. When pre-grouted prestressing strands are used for main tendon, more prestressing strands are required than when conventional multiple strands are used. Numerous prestressing strands therefore should be anchored in a limited anchorage region. Hence, attention should be paid in design for the arrangement of pre-grouted prestressing tendons and details of anchorage. This book entitled Prestressed Concrete Design aims to give an overview of the recent evolution in the design and construction of prestressed concrete worldwide. Several major trends are outline. A number of innovative techniques have been described to enhance both the structural performance and the durability of concrete. It will also address and focus on the extent to the use of structural and precast ecoefficient concretes in the applications which have been developed comply with current standards."