The course introduces methods and non-destructive techniques to investigate: buildings, infrastructures, foundations and the near-subsurface. The student will learn: the physical principles at the basys of non destructive methods so that they will be able to choose the proper technique in order to get the required information and to be aware of the result reliability. Parameters and acquisition procedures will be presented so that the student can design and perform a measurement survey. During the class the students will see many examples of non-destructive investigations applied to constructions and they will practice with equipment within the campus.