Antimicrobial susceptibility tests (ASTs) are massively run in clinical microbiology laboratories. By time there is a great microbial challenge therefore, some authors going so far as to suggest that we are approaching a post antibiotic effect era. This laboratory guide devoted to support clinical experience of bacteriologists and whom dealing with ASTs. Methods, results inter-pretation, evaluation of sensitivity tests were fully explained and supported with figures and color plates in addition to tables of antibiotics grouping and drug selection according to type of microorganisms and specimen source.