Orange County Medical Association
- Professional organization for physicians. Activities, membership information, and legislative updates.
- http://www.ocma.org/

Orange County Health Needs Assessment
- A collaboration of public and private sector policymakers that attempt to conduct a comprehensive health assessment of Orange County. Executive Summary, history, and monthly newsletters.
- http://www.ochna.org

Mental Health Association of Orange County
- Information on mental illnesses as well as volunteer opportunities in the area.
- http://www.mhaoc.org/

Irvine Health Foundation
- A non-profit grantmaking foundation whose goal is to improve the health and well-being of the residents of Orange County. Publications, lectures, and information about grant applications.
- http://www.ihf.org/

The HealthCare Foundation For Orange County
- The Foundation's mission is to improve the health of the neediest and most underserved residents of Orange County. Includes programs, calendar, investing and volunteer opportunities.
- http://www.hfoc.org/

Down Syndrome Association of Orange County
- Non-profit organization providing support and information to families, educators, doctors, hospitals, lawyers, geneticists, and family planners.
- http://www.dsaoc.org