Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

Mark J Siemens, LCSW

Individual provider Clinical Social Worker · NPI 1598700429

Mark J Siemens, LCSW is a Clinical Social Worker in Eugene, Oregon. Licensed in Oregon. Registered with an NPI since 2006.

Licensed in
OR
In the registry since
2006
What do these letters mean?
LCSW — Licensed Clinical Social Worker
A social worker licensed to diagnose and treat mental health conditions independently.

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Practice location Address checks out

1200 Hilyard St
Eugene, OR 97401-8122
Phone: (541) 744-0828
Fax: (541) 687-6214
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Clinical Social Worker (primary) Taxonomy 1041C0700X · Licence 002051 (OR)

Record details

NPI number1598700429
Entity typeIndividual (Type 1)
GenderMale
Credentials LCSW
Sole proprietorNo
NPI enumeratedJune 17, 2006
Last updated in NPPESJuly 2, 2012
Mailing addressPo Box 24410, Eugene, OR 97402-0451

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