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Customer Service Live Agent hours:
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Phone: +1.610.688.0100
Toll Free (US): 877.447.1888
Fax: +1.610.688.0700 

Mailing Address
Clinical and Laboratory Standards Institute
PO Box 334
Malvern, PA 19355

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Clinical and Laboratory Standards Institute
PO Box 645766
PITTSBURGH, PA 15264-5255 

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Lockbox Number 645766
500 1ST AVE
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CLSI reserves all rights to all content of CLSI standards, guidelines, and all other CLSI products and materials. Any entity, person, or business who desires to copy, duplicate, replicate, reproduce, extract, present, or otherwise communicate any content of CLSI standards, guidelines, or other CLSI products or materials shall obtain express written consent from CLSI. Contact Permissions@clsi.org

Media or Partnership Inquiries

Let’s collaborate. We love working with journalists and partners that share our mission to help make the world safer and healthier. Contact Marketing@clsi.org and let’s figure out how to work together. 

Brand Guidelines

CLSI’s mission is to develop and promote safe and effective laboratory practices around the world. Our aim is to ensure consistency in diagnostic practices, the highest quality of care, and continued innovation and improvement in clinical and laboratory testing and tools. Our brand identity is built on over 50 years of thought leadership and collaboration in an environment that is constantly evolving and adapting, and a world that is becoming both increasingly interconnected and highly diverse. This brand guide is a living resource intended to help share principles and guidelines that define how we show up in the world.

Want to Get Involved?

There are lots of ways to participate in standards development – from volunteering on a committee to commenting and voting on standards to ensure they meet laboratory requirements.