Elaine Fulton, assistant director of the Scottish Library Association, said hard-pressed authorities had saved money by taking away the shift allowances given to librarians for working extended days. The result was an end to 9am 9pm opening hours.
A UK-wide survey conducted by The TES and Lancaster University has found that cuts in hours are restricting library use. More than a quarter of those interviewed wanted longer opening.
Of these, almost half wanted to use a library later in the day, and a similar number favoured Saturday or Sunday opening. A survey of local authorities found that only three out of 55 had any libraries open on Sunday.
Across England and Scotland councils are three times more likely to have reduced spending on libraries in the last five years than raised it. In Glasgow and North Yorkshire, the budget has been cut by more than a third.
Ms Fulton said councils had to recognise that libraries should be open "when communities want to use them", and the requirement might differ from place to place Evening opening would make sense in commuter areas.
Some libraries are experimenting with self-issue machines and by using a smart card borrowers could gain access to a secure area.
Martyn Wade, director of libraries in Glasgow, said the settlement of the recent staff dispute provided for an extension of opening hours from September and a move towards "tailoring" hours to meet the needs of different areas.
The TES campaign is intended to reverse the cuts of recent decades and make public libraries once again a first-class service.
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