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Leadership Team

  • Betsy Lenhart Cooksey

    Elizabeth Lenhart-Cooksey, LCSW-C, LCADC

    Clinical Services Director
    (301) 327-2555 ext 805
    blenhart-cooksey@pyramidwalden.com

    Betsy has been working in the clinical and administrative aspects of the behavioral health field since 1994. She holds a MSW from the University of Maryland School of Social Work and a MA in Counseling Psychology from Bowie State College. Betsy completed her undergraduate work at Towson State University. She is a Licensed Certified Social Worker-Clinical (LCSW-C) and a Licensed Certified Alcohol and Drug Counselor (LCADC). Betsy’s professional experiences include clinical work in private practice and in day treatment programs. She has also served as the Director of Family Support Services at Hospice of St. Mary’s.

    In 1999, Betsy joined the Walden staff as a Clinical Services Coordinator in the substance use treatment program. Since that time, she has held positions of increasing responsibility to include Program Supervisor, Residential Services Coordinator, Outpatient Treatment Supervisor. In 2011, Betsy became Walden's Clinical Services Director. As Clinical Services Officer, Betsy has a unique opportunity to assure that the individuals and families seeking treatment with Walden receive the highest quality of clinical care possible. She is also actively involved in representing Walden with community partners and stakeholders.

  • Kori Olszewski

    Kori Olszewski, LCSW- C, CAC-AD

    Director of Residential Services
    (301) 327-2555 ext 882
    KOlszewski@pyramidwalden.com

    Kori Olszewski is Residential Director for Walden. She earned her Bachelor’s and Master’s degree from Southern Illinois University. She is a Licensed Certified Social Worker-Clinical and is also a Certified Addiction Counselor, Alcohol and Drug Counselor in the state of Maryland. Mrs. Olszewski started with Walden in June of 2007 providing outpatient addiction treatment to youth and adults in group and individual settings. She has also provided inpatient care in residential treatment settings and as a treatment provider in a detention center treatment setting.

    Mrs. Olszewski was a key member in the implementation of an adult recovery community center and recovery housing program, and has worked closely with the juvenile and adult drug court programs in St. Mary’s county, supervising the treatment of clients in those programs. Mrs. Olszewski has specialized training in an array of evidenced-based practice models, as well as knowledge of addiction treatment placement criteria that best assists with the correct level treatment placement to support recovery from addiction.

    Prior to taking her current position, Mrs. Olszewski's management roles with Walden included work as Quality Assurance Manager and as Clinical Manager for Walden's Outpatient Treatment program in Lexington Park, Maryland.

  • Jessica Jolly

    Jessica Jolly, LCSW-C

    Director of Outpatient Services
    (301) 327-2555 ext 872
    jjolly@pyramidwalden.com

    Jessica Jolly is Outpatient Director for Walden. Ms. Jolly earned her Bachelor’s degree from Kutztown University of Pennsylvania and her Master’s of Social Work degree at West Chester University of Pennsylvania. She is a Licensed Certified Social Worker-Clinical with additional training from the Maryland Center of Excellence on Problem Gambling, the International Association of Trauma Professionals, and FEMA Emergency Institute.

    Prior to moving into her role as Outpatient Director, Ms. Jolly served Walden in a variety of roles, including Clinical Outpatient Manager, Behavioral Health Therapist, and Lead Addictions Counselor (residential.) Ms. Jolly also brings her previous work experience as a psychotherapist and in supportive roles with young people with disabilities to the Walden team. She recently served as a board member of the National Association of Social Workers.

  • Keesha Vines

    Keesha Vines, LCPC, NCC

    Access Manager
    (301) 327-2555 ext 826
    kvines@pyramidwalden.com

    Keesha Vines is Access Manager for Walden. She earned her Bachelor’s degree from the University of North Texas and her Master’s degree from the Chicago School of Professional Psychology. Prior to taking her position as Access Manager in 2018, Ms. Vines served in Assistant Clinical Manager and therapist roles in Walden’s residential treatment program. She brings additional experience garnered in family and community mental health clinics to the Walden team.

  • Kristi Burns

    Kristi Burns, LCPC, LCADC

    Clinical Supervisor, Anchor Program
    (301) 327-2555 ext 834
    kburns@pyramidwalden.com

    Kristi Burns is the Clinical Supervisor for Residential Services at our Charlotte Hall (Anchor) campus. She earned her Bachelor’s and Master’s degrees from Frostburg State University. She is a Licensed Clinical Professional Counselor and is also a Licensed Clinical Alcohol and Drug Counselor in the state of Maryland. Her career with Walden began in June of 2005 as a residential treatment counselor.

    Mrs. Burns has continued her professional growth with Walden in a variety of residential positions to include case management and program supervision and management of long term care residential programs and outpatient programs. Mrs. Burns is a key team member in the initial and ongoing implementation of 3.1 and 3.5 levels of care in the Charlotte Hall location. She has specialized in creating a treatment program that is based on clients’ individualized needs. Mrs. Burns is committed to assuring that residential programming matches the ever-changing needs in the community to access and powerfully benefit from care.

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    Anni Christensen, LCPC, CAC-AD

    Clinical Supervisor, Outpatient Programs
    (301) 327-2555 ext 849
    achristensen@pyramidwalden.com

    Anni Christensen is Walden’s Clinical Supervisor for Outpatient Services in our Lexington Park location. She earned her Master’s in Psychology from California State University and her Master’s in Management from Florida Institute of Technology. She completed her Bachelor’s in Behavioral Science from University of Maryland but began her educational career with a degree in Social Psychology from the Socialpedagogisk Seminarium in Aolborg, Denmark. Professional experiences include roles with Walden as a program supervisor and addition counselor in both outpatient and residential treatment settings as well as a counselor in rehabilitation settings.

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    Joanna Grapuman, LCPC

    Clinical Supervisor, Outpatient Programs
    (301) 327-2555 ext 883
    jgraupman@pyramidwalden.com

    Joanna Graupman is Walden’s Clinical Supervisor for Outpatient Services in our Charlotte Hall and Waldorf locations. She earned her Bachelor’s from Randolf Macon Women’s College and her Masters’ of Arts in Counseling from Eastern Mennonite University. Her career at Walden has included work as a substance use counselor, trauma counselor, and manager of multiple program areas at Walden. Specialty areas of interest include trauma-informed care and spirituality and the counseling relationship.

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    Michelle Northam

    Clinical Supervisor, California Residential Campus
    (301) 327-2555 ext 844
    mnortham@pyramidwalden.com

    Michelle Northam is Clinical Supervisor at Walden’s California campus. Her various professional experiences include special education teacher, victim advocate and prevention educator, behavioral health therapist and early childhood mental health consultant. With 10 years of experience in the field, she has a passion for collaboration, team building, as well as supporting and encouraging others to achieve their highest potential.

  • Laura Webb

    Laura Stewart Webb, M.A.

    Executive Director
    (301) 327-2555 ext 804
    lwebb@pyramidwalden.com

    Laura Stewart Webb is Walden’s Executive Director. Laura earned her Bachelor’s from University of North Carolina-Wilmington and did her Master’s work in Adult and Community Education at the Indiana University of Pennsylvania. Her service at Walden has also included management roles in recovery support and community engagement. Laura was a central team member to implementation and operations of Walden’s peer support, adult recovery community center and adolescent clubhouse programs. She has also been integral to the design of multiple new or enhanced initiatives into the community in areas such as problem-solving courts, integrated care, peer and recovery support, and trauma-informed care.

    Laura is a trained mediator and restorative practice facilitator and a trainer for CCAR’s Recovery Coach Academy, Mental Health First Aid, Youth Mental Health First Aid and as a certified Upside Down Organization presenter. Prior to joining Walden in 2009, Laura worked in a Georgia-based continuum of care serving individuals impacted by homelessness. She has also worked in the adult literacy field and served in the United States Army.

  • Dr. Kathleen O'Brien, Ph.D.

    Dr. Kathleen O'Brien, Ph.D.

    Chief Development Officer
    (301) 327-2555 ext. 803
    kathleen@waldensierra.org

    Kathleen O. O’Brien, Ph.D., is currently Chief Development Officer of Walden. Previously, Dr. O'Brien served as Walden Sierra's Chief Executive Officer/Executive Director. She earned her Bachelor’s and Master’s degrees from the University of Maryland, and her doctorate in Clinical Psychology from LaSalle University. Dr. O’Brien began her rich career with Walden in 1973. She served as the Clinical Director from 1978 to 1990, when she became the Executive Director. Her commitment and dedication have been a driving force in the development and expansion of a multi-service behavioral health organization that is respected for service excellence at the state and national level.

    Dr. O’Brien plays a prominent role in her local and Maryland-wide community where she is a strong advocate for advancing understanding of addiction as a brain disease as well as the use of treatment approaches informed by brain-based and trauma-informed practices. Her career has included service on numerous boards and commissions. Currently, she is a gubernatorial appointee to the Behavioral Health Advisory Council and co-chair of the Forensics Committee for the Council. She is also a Governor’s Appointee to the Family Violence Council. Dr. O’Brien serves on the board of the Maryland Coalition against Sexual Assault and is President of the Maryland Alcohol and Drug Council board and has previously served as Chair of the Healthy St. Mary’s Partnership. She is a Weinberg Fellow and was a member of Leadership MD class of ’08.

  • Catherine Briggs

    Vice President of Operations
    (301) 327-2555
    cbriggs@pyramidhc.com

    Catherine Briggs has been working in the field of behavioral health operations for more than 25 years, with a Bachelor’s Degree from Texas A&M University and a Master’s Degree in Health Administration from Penn State University. She has developed and managed treatment programs including residential, outpatient, and community-based services for individuals with mental health and substance use disorders. Catherine joined Pyramid Healthcare in 2014 and has focused on the development of treatment delivery systems in Pennsylvania and Maryland that provide the entire continuum of care.

  • There is no other treatment program I could have asked to help me succeed.

    - Anonymous

  • All the staff has been incredible on my long road to recovery.

    - Anonymous

  • Walden treats each other like family and had an ear open at all times.

    - Anonymous

  • I thank God for Walden.

    - Anonymous

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Hope for Tomorrow
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