M23 Free
This guideline discusses the necessary and recommended data for selecting appropriate breakpoints and quality control ranges for antimicrobial agents.
Find the latest news and updates from our microbiology standards committees.
Why Use CLSI Breakpoints? Free Resources AST Rationale Documents AST Subcommittee E-mail List
About the Microbiology Standards Subcommittees
View Meeting Files and Resources
View Educational Resources
This guideline discusses the necessary and recommended data for selecting appropriate breakpoints and quality control ranges for antimicrobial agents.
Quickly reference the most trusted AST veterinary breakpoint tables as a convenient, complimentary supplement to the AST VET01 document.
With these read-only web versions of M100 and M60, you can now quickly reference the most trusted AST and antifungal breakpoints from anywhere with an Internet connection. Available online as a convenient companion to our M100 document and M60 document.
Our rationale documents provide the scientific reasons behind the AST subcommittee’s decisions, along with documentation of the standardized data and methods used to determine breakpoints.
Hear directly from our volunteers about their experience volunteering on CLSI AST Subcommittees.
![]() |
![]() |
January-February 2021
Virtual
June 24–29, 2021
San Diego, California, USA
August-October 2020
Virtual
January 23–26, 2020
Tempe, Arizona, USA
Staff Liaison
Marcy L. Hackenbrack, MCM, M(ASCP)