This manual's main intention is to give an easy to use laboratory companion to students of veterinary microbiology, biomedical laboratory technology, as well as all those people involved in laboratory investigation cum diagnosis of microbial diseases of animals. It covers a wide range of basic manipulative techniques and test procedures carried out in diagnostic laboratories, including microscopy, aseptic techniques, isolation and pure culture techniques for bacteria and fungi, procedures for conducting and interpreting the various biochemical tests, as well as tables one can use to systematically distinguish between the various families, genera, species, etc. of pathogenic bacteria and fungi affecting animals. Procedures for conducting and interpreting antimicrobial susceptibility tests for bacteria are also given in a manner that that can easily be understood by undergraduate students. To comprehensively capture the laboratory aspects of pathogenic bacteria and fungi one is advised to read this manual together with 'Bacteriology and Mycology Handbook' published by the same authors.