Brandi Orth will replace Victor Salazar as the county's top elections official.
Orth was sworn in by Judge Brad Hill Tuesday morning on her family Bible, which her mother brought in from North Carolina.
Orth was a policy analyst who worked for Fresno County for 18 years.
Her new responsibilities include overseeing elections, voter registration and a number of county clerical services.
The job pays $118 thousand dollars a year, plus benefits.
Orth was appointed to the position by the Board of Supervisors last week, just days after Salazar's unexpected resignation, which left the county with no one to manage the busy election year ahead.
Salazar cited health issues as his primary reason for leaving but said a lack of funding for the office also contributed to his decision.