Physician Profile
Matthew C. Williams, MD
Unclaimed ProfileAbout Dr. Williams
Based in Mill Valley, CA, Matthew C. Williams, MD is listed in the NPI registry under child & adolescent psychiatry. Matthew graduated from Georgetown University School of Medicine in 2021. Matthew is also listed as specializing in psychiatry. Medicare claims data shows Matthew provided 168 services to 95 patients. The services billed most often include subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes, psychotherapy with evaluation and management visit, 30 minutes, and psychiatric diagnostic evaluation with medical services.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it.
Education & Training
Specialty
Credentials & Licensing
License numbers are what the provider reported to NPPES when the NPI was issued or updated. NPPES does not verify licensure; confirm current standing with the state licensing board.
Medicare information
Exactly as CMS reports it (National Downloadable File, Opt-Out Affidavits, Order & Referring). Not an insurance directory; confirm coverage with the office.
Contact Information
- (415) 381-1690
- Email not available
Practice Locations
655 REDWOOD HWY FRONTAGE RD STE 261
Mill Valley, CA 94941
Conditions Commonly Evaluated or Treated
Within Child and Adolescent Psychiatry generally. Availability varies by clinician, training and location — this profile has not been claimed, so nothing here is a personal claim by the provider.
Conditions
Most searched conditions
- Autism
- Childhood anxiety
- Pediatric ADHD
- Teen depression
Addiction & Substance Use
- Teen Substance Abuse
Anxiety
- Agoraphobia
- Perfectionism
Anxiety & Compulsions
- Child Not Talking at School
- Childhood Anxiety and Depression
- OCD in Children and Teens
- Panic Attacks in Kids
- Skin picking and hair pulling
- Social anxiety disorder
- Specific phobias
Attachment and trauma
- Attachment Issues
Behavior
- Compulsive Lying in Kids
- Compulsive Stealing in Children
- Conduct disorder
Behavioral Problems
- Oppositional defiant disorder
- Screen Addiction
- Sensory Overload Meltdowns
- Severe Temper Tantrums and Meltdowns
Crisis & Mood
- Bipolar Disorder in Teens
- Extreme Mood Swings and Emotional Dysregulation
- Hearing Voices and Paranoia in Teens
- Self-harm
- Suicidal thoughts
Developmental & Elimination
- Bedwetting
Developmental & Identity
- Gender Identity Distress in Youth
Dissociation
- Dissociation and depersonalization
Eating & Body Image
- Anorexia nervosa
- Body image issues
- Extreme Picky Eating and Food Aversion
Eating disorders
- Binge eating
- Eating disorders
Elimination disorders
- Poop Accidents and Withholding
Mood and personality
- Borderline Personality Traits in Teens
- Persistent depressive disorder
Neurological & Tics
- Tics and Tourette Syndrome
Neuropsychiatric
- PANDAS and PANS
School & Learning
- School refusal
Sleep
- Night Terrors and Frequent Nightmares
Sleep & Routine
- Sleep Problems in Kids
Stress and physical symptoms
- Adjustment disorder
- Somatic symptom disorder
Substance use
- Marijuana Addiction
- Vaping Addiction
Trauma & Stress
- Bullying Trauma and Distress
- Childhood Trauma and PTSD
- Divorce and Family Change Distress
- Grief and Loss in Children
Procedures & services
Most searched procedures
- Autism testing
- Medication management
- Psychiatric evaluation
Addiction Care
- Adolescent Substance Abuse Counseling
Behavioral Interventions
- Bedwetting and Soiling Behavioral Therapy
- Behavioral Sleep Coaching for Children
- Habit reversal training
Behavioral support
- Pediatric Behavioral Modification Plan
Brain stimulation
- Teen TMS Therapy
Crisis Care
- Crisis Intervention and Safety Planning
- Inpatient and Residential Care Placement Assessment
Eating & Specialty
- Family-Based Eating Disorder Treatment (FBT)
Eating disorders
- Eating Disorder Medical Monitoring
Evaluation and visits
- Adolescent Psychiatric Clearance
- Child Functional Behavior Assessment Consultation
- Comprehensive Child Diagnostic Interview
- PANS and PANDAS Psychiatric Assessment
- Virtual Child Psychiatry Visit
Medication management
- Child Psychiatric Medication Management
- Teen Ketamine Infusion Consultation
Parent Support
- Parent coaching
- Sensory and Emotional Co-Regulation Coaching
School & Advocacy
- IEP and 504 Plan Psychiatric Consultation
- School Refusal Reintegration Therapy
Screening and testing
- Teen Depression and Anxiety Screening
Skill Building
- Anger Management for Kids
- Executive Function Coaching
- Social Skills Groups
Specialty Treatments
- Gender-Affirming Mental Health Support
- Pediatric Neurofeedback and Biofeedback
Substance use
- Adolescent Relapse Prevention Planning
Talk Therapy
- Acceptance and Commitment Therapy (ACT) for Teens
- Childhood Trauma Therapy (TF-CBT)
- Cognitive Behavioral Therapy (CBT) for Kids
- Dialectical behavior therapy (DBT)
- Exposure and Response Prevention
- Family therapy
- Grief Counseling for Children
- Play therapy
- Teen Support Groups
Testing & Assessment
- ADHD Testing
- DNA drug response testing
- Psychiatric Second Opinion
- Psychoeducational Testing
Therapy
- Animal-Assisted Therapy for Kids
- Art Therapy for Children
- Attachment-Based Child Therapy
- Interpersonal Psychotherapy for Teens (IPT-A)
- Mindfulness for kids and teens
- Music Therapy for Children
- Parent-child interaction therapy
- Teen DBT Skills Group
Trauma & Specialty
- EMDR Therapy for Children
Procedures Most Often Billed to Medicare
168 services · 95 patients · 3 distinct codes
| Procedure | Type | Code | Services | Compared with peers |
|---|---|---|---|---|
| Psychotherapy with evaluation and management visit, 30 minutes | Treatment | 90833 |
73 | As often as other peers in Child & Adolescent Psychiatry |
| Psychiatric diagnostic evaluation with medical services | Treatment | 90792 |
15 | |
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes | Office visit | 99233 |
80 | More often than most peers in Child & Adolescent Psychiatry |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other child & adolescent psychiatry specialists at this location 1
Same specialty, same street address — most likely the same department or group.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
Other child & adolescent psychiatry specialists in Mill Valley 1
Same specialty, same city.
More connections — 23 related providers in 3 groups
Trained at Georgetown University School of Medicine 7
Other providers in the same specialty who trained at the same institution.
Class of 2021 at Georgetown University School of Medicine 8
Providers who graduated from the same medical school in the same year.
Also performs Psychotherapy with evaluation and management visit, 30 minutes 8
Providers in CA who bill this service to Medicare most often.
Common questions
What does Dr. Williams specialize in?
Dr. Williams is a child & adolescent psychiatry in Mill Valley, CA. That is the designation recorded for this NPI in the federal registry.
NPI registry
Where is Dr. Williams located?
Dr. Williams is listed at 655 Redwood Hwy Frontage Rd Ste 261, Mill Valley, CA 94941. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
What is Dr. Williams's phone number?
The number on file is (415) 381-1690. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is the NPI for Dr. Williams?
Dr. Williams's National Provider Identifier is 1326626797. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Dr. Williams go to medical school?
Dr. Williams attended Georgetown University School of Medicine, graduating in 2021. This comes from the CMS National Downloadable File.
CMS public data
How much experience does Dr. Williams have?
Dr. Williams has 5 years experience. Calculated from a graduation year of 2021, reported in the CMS National Downloadable File.
CMS public data
What does Dr. Williams do most often?
According to Medicare billing data, Dr. Williams provides treatments such as psychotherapy with evaluation and management visit, 30 minutes and psychiatric diagnostic evaluation with medical services, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Is Dr. Williams's profile verified?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Williams. If this is you, claiming it is free.
Guide.md
Provider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.