“…Firstly, we may quote the studies developing an instrument for measuring quality management, assessing its validity and reliability, applicable only to service firms, defined as SERVQUAL Berry, 1985, 1988) or to industrial firms (Flynn, Schroeder and Sakakibara, 1994;Ahire, Golhar and Waller, 1996); and secondly, the studies which develop a valid, reliable quality measurement instrument, applicable to industrial and services firms (Saraph, Benson and Schroeder, 1989;Badri, Davis and Davis, 1995;Porter, 1995, 1996;Grandzol and Gershon, 1998;Quazi et al, 1998), shown in Table I. " Table I" This examination allows us to say, on the one hand, that the critical factors of TQM differ from one author to another and, therefore, there is no unanimous view of the key factors of TQM, and on the other hand, that in practice firms may follow known, accepted, standard models as a guide to carry out quality management. In spite of this, this review shows that there are common issues appearing in the three approaches analyzed, such as leadership, quality planning, human resource management (training, teamwork, ...), customer focus, process management, suppliers management and continuous improvement (information, analysis, ...).…”