Microbiology | Standards

CLSI has a longstanding globally trusted reputation for its diligent development of Microbiology and Antimicrobial Susceptibility Testing (AST) standards and guidelines on test methods and QC procedures. Additionally, CLSI annually creates and revises AST breakpoints to meet global public health challenges related to antimicrobial resistance. CLSI’s library of Microbiology standards and AST guidelines establish vital performance criteria and best practice guidelines for use in the clinical microbiology laboratory field.

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CLSI M100 - 2025 Preorder | Performance Standards for Antimicrobial Susceptibility Testing, 35th Edition

CLSI M100-Ed35 includes updated tables for the Clinical and Laboratory Standards Institute antimicrobial susceptibility testing standards CLSI M02| Performance Standards for Antimicrobial Disk Susceptibility Tests, 14th Edition (2024), CLSI M07| Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically, 12th Edition (2024), and CLSI M11 | Methods for Antimicrobial Susceptibility Testing of Anaerobic Bacteria, 9th Edition (2018).

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CLSI 2025 M100 Update Webinar | Implement CLSI M100 With Confidence

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CLSI M64 | Implementation of Taxonomy Nomenclature Changes, 1st Edition

CLSI M64 includes recommendations for implementing nomenclature changes for medically important bacteria and fungi that are identified and reported from clinical specimens, especially when testing for antimicrobial susceptibility.

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Procedure for Optimizing Disk Contents (Potencies) for Disk Diffusion Testing of Antimicrobial Agents Using Harmonized CLSI and EUCAST Criteria, 2nd Edition

CLSI M23S | Procedure for Optimizing Disk Contents (Potencies) for Disk Diffusion Testing of Antimicrobial Agents Using Harmonized CLSI and EUCAST Criteria, 2nd Edition

CLSI M23S describes the necessary technical steps for establishing the optimal disk content (potency) for single antimicrobial agents without the addition of enhancing or inhibiting substances.

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CLSI M23S2 | Process to Submit Disk Content (Potency) Data for Joint CLSI-EUCAST Working Group Review and Approval, 2nd Edition

CLSI M23S2 describes the process to submit disk content (potency) data to the joint CLSI-EUCAST working group for review and approval.

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