Libraries in Hertfordshire could have their opening times cut by a third in proposals aimed at ensuring they will not have to close down.
The county council is running a consultation on the impact of efficiency savings on the library service.
The council is hoping to keep all its buildings open and instead reduce the opening hours.
Libraries would open for 1,575 hours a week rather than the current 2,236.
It is also proposed to focus the mobile library service on rural areas.
Leader of the council, Robert Gordon, said: "We want to avoid closures but the financial realities have forced us to consider significant reductions in opening hours instead.
"We plan to stagger opening hours so that, even when your most local library is closed, another relatively local one will be open."
The seven-week consultation started on Tuesday.