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Dr. John Craig Williams Jr., PSY.D.

Clinical Psychologist in Livermore, CA · enumerated 2008 · practices at Brian Peter Quinn.

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

National Provider Identifier

1265600662

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Registry record

Entity type Individual (Type 1)
Name Dr. John Craig Williams Jr.
Credential PSY.D.
Sex Male
Practice address 1080 Concannon Blvd, Suite 170, Livermore, CA, 94550
Phone (925) 918-2469
Enumeration date Feb 19, 2008
Last updated in NPPES Feb 19, 2008

Taxonomy & licenses

103TC0700X Clinical Psychologist Behavioral Health & Social Service Providers · License PSY20258 (CA) Primary
PSYD · Doctor of Psychology: A clinical doctorate in psychology focused on professional practice. About the PSYD 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 specialty is John Williams?
John Williams is registered in NPPES with the primary taxonomy of Clinical Psychologist. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-02-19.