CLSI MM19-Ed2—Establishing Molecular Testing in Medical Laboratory Environments provides a framework for decision-making and implementation of clinical molecular diagnostics and is intended for those in established medical laboratories that are implementing a molecular program for the first time. When implementing any diagnostic test, many factors should be considered before the test is available for use in patient care. CLSI MM19 focuses on the laboratory path of workflow, including safety and the QMS, with an emphasis on considerations for molecular diagnostics. An organized approach to strategic planning is presented, and relevant regulatory requirements and an implementation plan are discussed in detail. Importantly, special considerations are provided for each of the following molecular subspecialty areas: heritable diseases, oncology and malignant hematology, pharmacogenomics, and infectious diseases.

CLSI MM19-Ed2 replaces CLSI MM19-A, published in 2011. Several changes were made in this edition, including: 
• Updating and streamlining all content 
• Providing specific guidance on procedural, technological, and regulatory aspects of developing molecular testing within a routine medical testing environment 
• Providing specific guidance on important preexamination, examination, and postexamination aspects for heritable disease, oncology and malignant hematology, pharmacogenomic, and infectious diseases molecular testing subspecialties 
• Adding infrastructure and data retention requirements

CLSI MM19 provides an overview of how molecular diagnostics are implemented to support existing laboratory services. It provides general recommendations for establishing an appropriate testing environment in which molecular assays are developed and implemented. Because molecular diagnostics is multidisciplinary in nature, CLSI MM19 provides an overview of special considerations that are unique to identified subspecialties. Cross references to other CLSI documents providing assay technical details are included. 

CLSI MM19 is intended for use by medical laboratory professionals who understand the fundamentals of medical testing but are looking to expand testing by adding molecular methods to a currently existing medical laboratory. 

Assays and areas not covered include: 
• Paternity and forensics 
• Blood banking 
• Detection of bioterrorism agents that require biosafety levels 3 or higher 
• Preimplantation genetic diagnostics and screening