The selection of the antimicrobials for treatment is important because of their high cost, pharmacokinetic/pharmacodynamic relations and close association between resistance and overuse of these drugs. The Government Restriction Policy on the Antimicrobial Consumption, brings responsibility to the infectious disease specialist (IDS). In this respect IDS has important duty in eradication of infection, control and prevention of infection and developing appropriate antibiotic usage strategies. The problems will be solved by continues updating of knowledge on resistance mechanisms, drug interactions and host relationships.