| Alvarado-Gonzalez, Yanet | Contractor | Public Works | | |
| Alvidrez, Michael | Utilities Crew Chief | Utilities | 949-718-3419 | |
| Aman, Matthew | Public Works Inspector, Senior | Public Works | 949-718-1850 | |
| Amat, Alex | Fire Captain 112 Hours | Fire | 949-644-3104 | |
| Ambrose, Trevor | Lifeguard II | Fire | | |
| Andersen, Leonard | Facilities Maintenance Worker II | Recreation & Senior Services | | |
| Anderson, Bryce | Fire Captain 112 Hours | Fire | 949-644-3355 | |
| Anderson, Jennifer | Purchasing And Contracts Administrator | Finance | 949-644-3080 | |
| Anderson, Matthew | Fire Engineer 112 Hour | Fire | 949-644-3355 | |
| Anderson, Morgan | Recreation Leader, Senior | Recreation & Senior Services | | |
| Anderson, Steven | Department Assistant | Finance | 949-644-3032 | |
| Angeloff, Anne-Marie | Library Assistant | Library - City | 949-717-3861 | |
| Aniol, Hali | Fiscal Clerk, Senior | Finance | 949-644-3248 | |
| Appeldorn, Fletcher | Senior Pool Lifeguard | Recreation & Senior Services | | |
| Appeldorn, Gavin | Senior Pool Lifeguard | Recreation & Senior Services | | |
| Aquino, Dan | Civil Engineer - Plan Check, Principal | Community Development | 949-644-3292 | |
| Arciniega, Elizabeth | Recreation Coordinator | Recreation & Senior Services | 949-718-1828 | |
| Arciniega, Patrick | Contractor | Public Works | | |
| Arechiga, Samuel | Maintenance Operator | Municipal Operations | 949-718-3463 | |
| Arechiga-Camacho, Sonia | Fiscal Clerk, Senior | Finance | 949-644-3137 | |
