Our Staff

Eleftheria Tsavoussis, PMHCNS-BC
Owner, CEO & Psychiatric Clinical Nurse Specialist
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Suzanne Brennan-Nathan, LICSW, C.G.P.
Clinical Social Worker
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Chris Shaw, PMHNP-BC
Psychiatric Mental Health Nurse Practitioner
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Christine Aposhian, Ed.D, M.Ed.
Psychologist
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Susan Korber, PMHCNS-BC
Psychiatric Mental Health Nurse Practitioner
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Linda Simon LICSW
Clinical Social Worker

Marylouise Demick, PMHNP-BC
Psychiatric Mental Health Nurse Practitioner

Margaret (Meg) van Bael LICSW
Clinical Social Worker

Karen Kronenberg LICSW
Licensed Independent Clinical Social Worker
Karen Kronenberg is a (LICSW) who specializes in helping adults who are facing issues with depression, anxiety, grief and loss, relationship problems or other mental-health concerns. Prior to joining Waltham Behavioral Health, she served as a hospice social worker, ran a dual-diagnosis group at a Partial Hospital Program, and as a psychotherapist at different mental-health agencies prior to WBH. Mental Health Association. Karen specializes in using a combination of psychodynamic therapy, cognitive-behavioral therapy (CBT), dialectical behavioral therapy (DBT), and Emotionally Focused Therapy (EFT) in a warm, supportive environment while challenging clients as appropriate. She holds a B.A. in Human Services from the University of Massachusetts/Boston and an MSW from Simmons University’s Graduate School of Social Work.