Executive Leadership

Organization and Management

Bill Thomsen, Chief Executive Officer

I began my career with RSBCIHI in February 1996 as a temporary Property and Supply Clerk for several months before being hired to that permanent position. I then served as the Materials Management Officer for about three years. From there, the position of Quality Management Coordinator became available and I received a promotion to work in that capacity . Since February 2006, I have been honored to serve as RSBCIHI’s Chief Operations Officer under the leadership of the CEO. My educational background includes a Bachelor of Science Degree in Business Management from the University of Maryland and a Master’s Degree in Health Administration from the University of La Verne.

Mo Zayed, Chief Financial Officer

Mo Zayed has over two decades of experience as a financial leader, primarily working in the healthcare technology sector. Mr. Zayed has experience in multiple areas of finance, including strategic finance, treasury, risk management, accounting compliance, budgeting and planning, M&A and systems implementation. Prior to serving as RSBCIHI’s CFO, Mr. Zayed was a finance executive and CFO responsible for multiple entities ranging from startups to publicly traded companies. During his tenure with Cerner Corporation, he also served as Cerner’s Board of Directors representative at the American Pharmacy Alliance. Earlier on in his career, Mr. Zayed worked as a CPA for RSM, a leading national accounting firm. Mo earned a Bachelor of Arts Degree in Economics from Claremont McKenna College and an MBA in Finance and Information Systems from Case Western Reserve University.

Rosa Arambula, HR Director

Rosa Arambula is currently the Human Resources Director for Riverside San Bernardino County Indian Health since 2003. She has notable experience in strategic human resource planning, performance management, staffing, federal and state law compliance, employment contract negotiations, employee benefits, compensation, policy and procedures, HR management systems and payroll. Ms. Arambula holds a Bachelor’s degree in Business Administration: HR Management from Cal Poly, Pomona. Her career has spanned over three decades, and has included senior-level human resources management roles for health care companies. She has been a long standing active member in the Society of Human Resources Management (SHRM).

Information Technology Director

I have been the Director of Information Technology for Riverside San Bernardino County Indian Health since 1996. My experience is in Strategic Planning, Organizational leadership, and planning. Implementation of Practice Management and Electronic Health Records, Cybersecurity, Infrastructure design and development. Health Information Management, Patient Services and Registration, Implementation of Telecommunications, Telemedicine, Utilization Review. HIPAA Privacy and Security Laws.

My career has spanned over three decades including Executive Staff – Senior Level management roles for healthcare organizations including inpatient and outpatients’ medical centers.

Dr. Ferra, Clinical Services Director

Dr. Ramon Ferra was born in Cuba, and emigrated to the US in April of 1961. He and his family moved to Santa Ana, California in December 1963 and grew up there. He attended UC Irvine for a Bachelor’s Degree in Biological Sciences, then attended UC Irvine School of Medicine. Dr. Ferra attended residency training at LA County-USC Women’s Hospital for Obstetrics and Gynecology. He practiced in Arcadia, CA for 14 years before moving to the mid West and subsequently South Florida. His last duties before joining RSBCIHI was medical director of the OBGYN services at Mount Sinai Medical Center in Miami Beach, FL. Dr. Ferra has performed thousands of deliveries and gynecologic surgical procedures. He has trained medical students and residents in 4 major universities across the country. Dr. Ferra is board certified in OBGYN, and is a current member of the American College of Obstetrics and Gynecology. He enjoys travel, photography and cooking.


“ I am so proud to work with the Native American Population in Southern California, and I am grateful for that opportunity. I have learned so much about the culture, and the history. I will do my best to represent the needs and concerns of our clinic population.”