SUMMARYRetention for partial denture is accomplished mechanically by means of extracoronal retainers, retantive clasp terminal engaging the undercut area on the abutment teeth.In this article, all the conventional clasp designs as well as the types proposed by Ney Surveyor System have been explained in detail.The choice of clasp designs should be based upon biologic as well as mechanical principles in order to render a satisfactory service to the patient.