Aggie Alonso is an experienced executive with over 25 years of auditing experience. Aggie began his career in 1998 with the Los Angeles County Auditor-Controller’s Audit Division where he worked his way up from an Accountant-Auditor to the Division Chief of the Countywide Contract Monitoring. Aggie was responsible for managing approximately 40 professional auditors that primarily conducted fiscal, contract compliance, and other special reviews of County social service and health service contractors, and developed and oversaw the award winning Contractor Alert Reporting Database. Aggie currently serves as the Internal Audit Director and Chief Audit Executive for Orange County, the sixth largest County by population in the United States, with a budget totaling over $9 billion and employees totaling over 18,000. Aggie is responsible for managing Orange County’s internal audit function, whose primary objectives include developing and implementing risk-based audit plans focused on internal controls and information technology, and advising County management on appropriate internal controls, operational efficiency and effectiveness, and areas for process improvement. Aggie is a Certified Public Accountant, a Certified Internal Auditor, and holds a Certification of Risk Management Assurance from the Institute of Internal Auditors and a Bachelor of Arts degree in Accounting from California State University, Fullerton.

Jose Olivo serves as the Deputy Director of Internal Audit for Orange County.  Jose is responsible for leading audit professionals in providing independent and objective assurance and consulting services designed to add value and improve Orange County’s operations. Jose joined Orange County in November 2024 and has over 22 years of audit experience. Jose began his career in 2002 with the Los Angeles County Auditor-Controller’s Audit Division where he worked his way up from an Accountant-Auditor to Chief Accountant-Auditor. Jose is a Certified Information Systems Auditor and Certified Internal Auditor, and holds a Bachelor of Science degree in Computer Information Systems and Accounting from California State University, Dominguez Hills.

Michael Dean began his career in 1996, shortly after the establishment of the Internal Audit Department. With over 25 years of experience in Internal Audit, Michael is the Senior Audit Manager leading the Internal Control Audits team. Michael has performed audits, reviews, and consultation engagements in most County departments throughout his career. Michael is a Certified Public Accountant, a Certified Internal Auditor, Certified Information Systems Auditor and holds a Bachelor of Arts degree in Accounting from California State University, Long Beach.

Jimmy Nguyen is an Information Technology audit manager with over 12 years of IT/security auditing experience covering diverse industries. Jimmy has served the County of Orange since 2016 and is responsible for managing the IT audit team of the Internal Audit Department. Jimmy is a Certified Information Systems Auditor, Certified Fraud Examiner, Certified Ethical Hacker and holds a Bachelor of Arts degree in Information Systems & Decision Science from California State University, Fullerton. 

Gianne began her career in 2013 as an Accountant/Auditor with the Orange County Auditor-Controller’s (A-C) office, where she worked on federal/state program claims and performed cash handling audits for the Health Care Agency. She then joined the A-C’s Internal Audit Division in 2016 as a Senior Auditor, where she performed internal control audits (ICA). She is now an Audit Manager for the Internal Audit Department’s ICA team. Gianne is a Certified Internal Auditor and Certified Information Systems Auditor. She holds a Bachelor’s degree in Business Administration with an Accounting concentration from California State University, Fullerton.

Alejandra joined the County of Orange in 2015 and held various accounting positions within the Auditor-Controller’s office before joining the Internal Audit Department in 2019 as a Senior Auditor. Alejandra holds a Bachelor of Arts degree in Psychology and a Master of Science degree in Accountancy. 

Gabriela Cabrera began her public service with the County as an Accounting Intern for John Wayne Airport in 2013, shortly after earning her Bachelor’s in Business Administration with a concentration in Accounting from California State University, Fullerton. Subsequently, she worked as an Office Technician for Social Services Agency, an Accounting Technician for the Clerk-Recorder, and as an Accountant/Auditor and Senior Accountant/Auditor for the Auditor-Controller’s office. These roles taught Gabriela how unique department processes achieve common goals, as well as the importance of collaborating with different business areas to maximize the impact of our public service. Since 2019, Gabriela has applied these insights to the Internal Control Audits she performs as a Senior Auditor with the Internal Audit Department.

Stephany Franco has over nine years of experience in auditing and accounting with expertise in internal audit, fiscal monitoring, and governmental accounting. Stephany’s primary focus is conducting Internal Control Audits and Information Technology Audits for the County of Orange. Stephany holds a Bachelor of Arts degree in Economics and Accounting from the University of California, Santa Barbara.

Mary Ann began her career in the tax practice at PricewaterhouseCoopers.  Subsequently, she worked as an auditor at the HHS Office of Inspector General, where she performed a wide variety of audits involving not-for-profit and healthcare organizations, educational institutions, and entities subject to the Affordable Care Act (ACA) and Medicare regulations.  In 2022, Mary Ann joined the Internal Audit Department.  As a Senior Auditor, her primary focus is conducting internal control audits.  She holds a Bachelor of Science degree in Business Administration, with a concentration in Accounting from California State University, Los Angeles.

Tina started her career in the private sector before joining the County of Orange in 2017. After taking on various accounting roles within the County, Tina joined Internal Audit Department in 2023. Tina holds a Bachelor of Arts in Business Administration concentration in Accounting from California State University, Fullerton.