Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Daniel J. Volk, PHD

Clinical Psychologist in Mill Valley, CA · enumerated 2006 · practices at Asch Marriage and Family Therapy, Inc..

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

National Provider Identifier

1659342590

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Registry record

Entity type Individual (Type 1)

Name Dr. Daniel J. Volk

Credential PHD

Sex Male

Practice address 6 Knoll Ln, Suite F, Mill Valley, CA, 94941

Phone (415) 389-0235

Fax (510) 521-8253

Enumeration date Jan 30, 2006

Last updated in NPPES Mar 20, 2008

Taxonomy & licenses

103TC0700X Clinical Psychologist Behavioral Health & Social Service Providers · License PSY8948 (CA) Primary

PHD — Doctor of Philosophy: A doctoral degree; in healthcare often held by clinical psychologists and researchers. About the PHD credential

Other identifiers

Identifier	Type	State	Issuer
PSY8948	Other	CA	LICENSED PSYCHOLOGIST

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 Daniel Volk?

Daniel Volk 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.

Other providers at this practice address

Browse all →

Leeann Bartolini Clinical Psychologist · Mill Valley, CA NPI 1356564959 Matthew Blagys Clinical Psychologist · Mill Valley, CA NPI 1609095132 Anne Asch Marriage & Family Therapist · Mill Valley, CA NPI 1821411380 Sarah Wescott Marriage & Family Therapist · Mill Valley, CA NPI 1841747284 Mathew Metzgar Marriage & Family Therapist · Mill Valley, CA NPI 1467990812 Janet Okman Marriage & Family Therapist · Mill Valley, CA NPI 1972134419 Asch Marriage and Family Therapy, Inc. Clinical Psychologist · Mill Valley, CA NPI 1437728953

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-03-20.