The main purposes of this study are to understand the applicability and reliability of quality indicators in Taiwan's hospitals, and to explore the relationship among quality indicators. A structured questionnaire was designed and distributed to collect experts'opin-ions via Delphi technique. According to the response of 14 medical car quality experts, almost all currently used indicators are considered important and applicable, while hospital-acquired nosocomial infections is considered the most important quality indicator. However, only structural and a few outcome indicators are reliable. Factors affecting the reliability of quality measures can be classified into three categories-environmental, organizational and data problems. According to the empirical analyses, positive relationship are found among structural indicators except the rate of specialists. No consistent correlation can be found among trocess-outcome indicators except several death rates. Empirical findings are consistent with those experts' opinions. However, under current situation, there is no reliable and applicable outcome indica-tor which can be employed for hospital accreditation.(Chin J Public Health.(Taipei) :1997;16(2):133-142)