Operating from the Midway District San Diego office at 3851 Rosecrans Street in Point Loma, San Diego, the County of San Diego Immunization Program tracks vaccine-preventable disease, enforces school-entry immunization law under California Health and Safety Code sections 120325–120380, and administers the regional node of the California Immunization Registry known as CAIR2. The program transitioned from its legacy San Diego Regional Immunization Registry to the statewide CAIR2 platform in April 2022, giving authorized providers and school administrators a single web-based system to verify a patient's vaccination status — a clinical-data workflow that feeds into laboratory confirmation at facilities such as Sharp Rees-Stealy Point Loma Laboratory. Vaccines for Children enrollment enables participating clinics to administer federally purchased vaccines at no cost to uninsured and underinsured minors from birth through 18, closing the coverage gap that fuels outbreaks of measles, pertussis, and hepatitis in under-immunized communities. The Immunization Program partners with over 400 organizations through the San Diego Immunization Coalition, a public-private network active since 1991 that ranks among the oldest continuously operating immunization coalitions in the country. That coalition reach extends to transitional-housing populations served by Veterans Village of San Diego, where catch-up vaccination drives target residents whose medical records were disrupted by homelessness or military separation. The program's most complex operational lift involves coordinating mass-vaccination response during declared public-health emergencies, standing up point-of-dispensing sites across the county within 48 hours of an outbreak notification.