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

Dr. Michael Andrew Williston, PSYD

Individual provider Psychologist · NPI 1093090474

Dr. Michael Andrew Williston, PSYD is a Clinical Psychologist in Wilmington, Delaware. Qualified in 2011, 15 years ago. Practices with Christiana Care Health Services Inc, a 1,481-clinician group, works from 2 locations, accepts Medicare assignment and offers telehealth. Licensed in Delaware and Pennsylvania.

Years since qualifying
15
Licensed in
DE, PA
In the registry since
2011
Specialties on file
2
What do these letters mean?
PSYD — Doctor of Psychology
A doctoral psychologist trained primarily for clinical practice.

See every abbreviation used in this directory →

Practice location Address checks out

4000 Nexus Dr Ste NE3-100
Wilmington, DE 19803-3000
Phone: (302) 320-9771
Fax: (302) 623-7964
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 112 N Broad St, Philadelphia, PA 19102-1512 — (215) 568-0860

Specialties & licences

Psychologist (primary) Taxonomy 103T00000X · Licence B1-0011487 (DE)
Psychologist Taxonomy 103T00000X · Licence PS017269 (PA)

Record details

NPI number1093090474
Entity typeIndividual (Type 1)
GenderMale
Credentials PSYD
Sole proprietorNo
NPI enumeratedOctober 17, 2011
Last updated in NPPESJanuary 13, 2025
Certification dateJanuary 13, 2025
Mailing address112 N Broad St, Philadelphia, PA 19102-1512

Medicare enrollment

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

Medicare specialtyCLINICAL PSYCHOLOGIST
Medical schoolOTHER
Graduated 2011 (15 years in practice)
Group practice Christiana Care Health Services Inc — 1481 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

Other providers in Wilmington