[1] Summers was appointed by Mayor Rahm Emanuel on October 22, 2014,[2] and took the oath of office on December 1, 2014.

[citation needed] In that capacity, Summers led changes to provide performance management in every department, which Preckwinkle claimed in 2014 had saved the city $400 million annually.

[6] In his role as chief of staff for President Preckwinkle, Summers also steered the closure of a $487 million budget deficit while keeping the administration's promise to roll back the county sales tax, saving taxpayers more than $400 million a year.

Additionally, Summers aided in reforming the county's procurement rules and helped pave the way for a more sustainable health and hospital system.

In that role, he led the Emerging and Diverse Manager business, which invested over $2 billion with minority- and women-owned firms.