Dine Romero has been announced as the new leader of the Liberal Democrats on Bath and North East Somerset Council.
Ms Romero said: "I am honoured to take on the role of Leader of the Liberal Democrat Group and I am grateful for the confidence colleagues have shown in me.
"Councillor Paul Crossley has been an inspiring Leader to the Group over the last 13 years and will be a hard act to follow.
"I can confirm that the Liberal Democrat Group will be forming a Shadow Cabinet to better hold the new Conservative Council administration to account. We will announce the make-up of our Shadow Cabinet following the council AGM.
"With a Conservative government in power, local councils are likely to be hit by stringent funding cuts. The previous Liberal Democrat administration made it a priority to ensure that vital services were protected in the face of reduced grant funding – particularly services for vulnerable people.
"Over the next four years we will continue to stand up for residents and we will be a strong voice of opposition on the council."
Mr Crossley had been leader of the Lib Dem group since 2002.
He said: "Dine is a very experienced and capable councillor with a superb understanding of the workings of B&NES Council.
"As Cabinet member for Early Years, Children and Young People she showed exceptional leadership at a time of upheaval in schools and early years education. Dine has my utmost confidence as group leader."