Post-tensioning is a method of prestressing in which prestressing steel is tensioned after concrete has hardened. Prestress is to place a hardened-concrete member or an assembly of units in a state of compression before application of service loads; the stress developed by prestressing, such as by pretensioning or post-tensioning. Prestressed concrete is Structural concrete in which internal stresses have been introduced to reduce potential tensile stresses in concrete resulting from loads which are counteracted to a desired degree.

In reinforced concrete the prestress is commonly introduced by tensioning the tendons. This method produces more slender structural elements, less reinforcing steel, lighter elements with greater load capacity, more clear or spaces between the support elements. Its versatility allows a wide variety of uses in construction: Office buildings, housing, shopping centers, industrial floors.