<qa>  What is the current practice in Taiwan?Methods: During a stepwise change in the policy of the antimicrobial stewardship program in this hospital, the study will observe the differences between two standardized core strategies preauthorization vs prospective audit of ASP. Hospitalized patients aged 20 and above, requiring use of restricted antimicrobials will be recruited into the study. Signing of consent forms are waived since both strategies are already proven to be effective and are widely implemented in Taiwan and worldwide. Also, the evaluation of such policy changes will not impact on patient safety or patient rights. The conduction of the study will not require contacting patients and no clinical samples will be collected. All data required for analysis will be collected via a computerized patient care system. Patient data will be protected via de-linking. Patients will be excluded if admitted at or entered the intensive care unit within 48 hours of entry, and if infectious diseases consultation had been requested. Eligible patients will be randomized to either preauthorization, which is the current practice in the hospital; or prospective audit, that will be done at 48-72 hours after prescription, as is the current practice in other hospitals in Taiwan and worldwide. Managing physicians are not obligated to follow our advice and the investigators will not intervene in their management decisions. Primary outcomes include antimicrobial utilization, drug costs and patient outcomes such as length of stay and clinical improvement. The time spent on implementing these two strategies will be compared. 