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

Dr. Marianne O'Leary, PHD

Individual provider Psychologist · NPI 1720147374

Dr. Marianne O'Leary, PHD is a Clinical Psychologist in Ellicott City, Maryland. Qualified in 1993, 33 years ago. Practices as a sole proprietor, accepts Medicare assignment and offers telehealth. Licensed in Maryland.

Years since qualifying
33
Licensed in
MD
In the registry since
2006
What do these letters mean?
PHD — Doctor of Philosophy
A research doctorate. In healthcare it usually sits alongside a clinical licence.

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Practice location Address checks out

3355 Saint Johns Ln Ste F
Ellicott City, MD 21042-2605
Phone: (410) 465-5520
Fax: (410) 480-0110
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Psychologist (primary) Taxonomy 103T00000X · Licence 03270 (MD)

Record details

NPI number1720147374
Entity typeIndividual (Type 1)
GenderFemale
Credentials PHD
Sole proprietorYes
NPI enumeratedDecember 8, 2006
Last updated in NPPESJuly 8, 2007

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyCLINICAL PSYCHOLOGIST
Medical schoolOTHER
Graduated 1993 (33 years in practice)
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

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