Gloucestershire's Police and Crime Commissioner (PCC) has appointed Rod Hansen as the force's new temporary chief constable.
He has taken the 12-month post following the retirement of Suzette Davenport last month.
PCC Martin Surl said the contract's length "reflected possible fundamental changes" to "key blue light services".
Mr Hansen has been Gloucestershire's deputy chief constable since 2013 after a career with Avon and Somerset police.
He said he wanted to "provide security, stability and vision for the constabulary" over the next year.
"I believe policing starts and ends in our neighbourhoods and one of our 'must wins' is around redefining what neighbourhood policing looks like in the 21st Century," he said.
Mr Surl said his decision to appoint a temporary chief constable had been influenced by "uncertainty over the future of the fire service".
He said: "The government is keen to see if a closer alignment would benefit both fire and police and lead to an even better service for the people of Gloucestershire.
"I have an open mind but if that proves to be the case, the responsibilities of the chief constable in 12 months' time could be very different to what they are today."
BBC West home affairs correspondent - Charlotte Callen
Rod Hansen has been appointed temporary chief constable for 12 months as there are ongoing discussions about whether the police and fire brigades might merge in the future to save money.
The government has said the services should discuss working together if it made financial sense. Rod Hansen made it clear to the BBC that he would like to do the job permanently if, or when, it is advertised.
For now, he's managing the force at a time of further cuts and following a critical HMIC report it will be a busy 12 months.