The California Department of Public Health’s (CDPH) Medical Marijuana Identification Card Program (MMICP) was established to create a state-authorized medical marijuana identification card (MMIC), along with a registry database for verification of qualified patients and their primary caregivers. Participation by patients and primary caregivers in this MMICP is voluntary. The MMICP web-based registry allows law enforcement and the public to verify the validity of a qualified patient or primary caregiver’s MMICP as authorization to possess, grow, transport, and/or use medical marijuana within California.