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

By Your Side, LLC

Organization Behavior Analyst · NPI 1922233923

By Your Side, LLC is a Behavior Analyst in Darien, Illinois. Registered with an NPI since 2009.

In the registry since
2009
Specialties on file
2
What do these letters mean?
LLC — Limited liability company
A form of business registration, not a clinical qualification.

See every abbreviation used in this directory →

Practice location Address checks out

8201 Cass Ave
Darien, IL 60561-5314
Phone: (630) 590-5571
Fax: (630) 326-7175
Show map & directions

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

Specialties & licences

Behavior Analyst (primary) Taxonomy 103K00000X
Speech-Language Pathologist Taxonomy 235Z00000X

Record details

NPI number1922233923
Entity typeOrganization (Type 2)
Organization subpartNo
Authorized official Matthew Sullivan — Chief Financial Officer · (630) 590-5571
Other names By Your Side; By Your Side
NPI enumeratedMay 19, 2009
Last updated in NPPESFebruary 4, 2021
Certification dateFebruary 4, 2021
Mailing address8201 Cass Ave, Darien, IL 60561-5314

Other providers in Darien