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Ms. Karen Duffy, MFTI

Marriage & Family Therapist in Petaluma, CA · enumerated 2010.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1144551789

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Registry record

Entity type Individual (Type 1)
Name Ms. Karen Duffy
Credential MFTI
Sex Female
Practice address 1500 Petaluma Blvd S, Petaluma, CA, 94952
Phone (707) 765-8488
Fax (707) 765-8482
Enumeration date Jan 21, 2010
Last updated in NPPES Jan 21, 2010

Taxonomy & licenses

106H00000X Marriage & Family Therapist Behavioral Health & Social Service Providers · License IMF51997 (CA) Primary

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Where does Karen Duffy practice?
The practice location on file with NPPES is in Petaluma, CA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Karen Duffy?
The National Provider Identifier (NPI) for Karen Duffy is 1144551789, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2010-01-21.