Debbie Arnold will join the Board of Supervisors on Jan. 7 at a ceremony during which incumbents Adam Hill and Frank Mecham will be sworn in to a second term.
South County Supervisor Paul Teixeira, who has served as vice-chair this year, will become board chairman.
The brief ceremony begins at 11:55 a.m. in the Board of Supervisors chambers in the new county government building, 1055 Monterey St., San Luis Obispo.
Arnold will replace Jim Patterson, a two-term supervisor whom she defeated in his bid for re-election in 2012. She will be the first woman on the board since 2007, when Shirley Bianchi retired.
A regular Board of Supervisors business meeting will follow at 9 a.m. on Jan. 8.