Former Wigan Athletic boss returns to old stomping ground
Cook, who resigned his post as Latics boss in the summer of 2020 after the club was placed into administration and relegated to League One, guided the Spireites to the League Two title and the League One play-offs during his previous spell, alongside Leam Richardson.
The duo moved on to Portsmouth, whom they guided to the League Two title in 2017, before moving to Wigan.
The Spireites are now in the National League, although they are flying high in second place this term.
Danny Webb will be his assistant.
"We are delighted to welcome Paul back to the club," said chief executive John Croot.
"He enjoyed great success here previously and to secure someone with his impressive track record is a real coup.
“Paul was our number one target when we began our search for a new manager and we are sure that our supporters will share our delight that he has agreed to take the role.
“Danny Webb is looking forward to working with Paul as part of the new management team.”
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