Due to budget cuts, Chicago's branch libraries were scheduled to be closed for four hours on Monday mornings during the school year.
Emanuel and Library Commissioner Brian Bannon said the department will adopt a "flexible staffing plan" to allow 76 neighborhood branches to offer full day service on Mondays without additional cost.
"We are not only re-establishing Monday morning hours during the school year, we are honoring the promise that library offers to the children and adults who depend on it," Emanuel said in a prepared statement.
Rather than using one staffing model for all branches, the department took into consideration circulation, foot traffic, technology use, and reference needs to determine each branch's particular needs, according to the city.
That approach will allow the city to re-allocate staff positions and fill vacant positions with a mix of full- and part-time positions, according to Bannon.
Bannon, the former chief information officer for San Francisco's public libraries, took over the Chicago system in March.
He followed longtime Commissioner Mary Dempsey, who resigned after 18 years at the helm. Dempsey's departure followed a tumultuous few months that saw Chicago's 76 branch libraries briefly shut their doors on some weekdays because the Emanuel administration and the union representing most library employees could not reach agreement on a plan to keep them open by having librarians work six days each week.