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Ms. Mary B Obrien, LCSW

School Social Worker in Northbrook, IL · enumerated 2007.

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

National Provider Identifier

1558541276

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Registry record

Entity type Individual (Type 1)
Name Ms. Mary B Obrien
Credential LCSW
Sex Female
Practice address 350 Lee Road, Northbrook, IL, 60062
Phone (847) 562-2100
Fax (847) 562-2112
Enumeration date Nov 9, 2007
Last updated in NPPES Nov 9, 2007

Taxonomy & licenses

1041S0200X School Social Worker Behavioral Health & Social Service Providers Primary
LCSW · Licensed Clinical Social Worker: A social worker licensed for clinical practice including mental-health therapy. About the LCSW credential

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

What is the NPI number for Mary Obrien?
The National Provider Identifier (NPI) for Mary Obrien is 1558541276, a Type 1 (individual) record in the CMS NPPES registry.
Where does Mary Obrien practice?
The practice location on file with NPPES is in Northbrook, IL. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-11-09.