Rahm Emanuel's closest confident, David Spielfogel, is flying the city of Chicago coup... No need to stay on a sinking ship

One of Rahm Emanuel's most trusted aides announced Thursday that he's departing City Hall after nearly five years by the mayor's side.

David Spielfogel, Emanuel's senior adviser and closest confidant on staff, said he'll leave his government post next week to start a technology company. Spielfogel has served as a key deputy to Emanuel since May 2011, making him one of the few top aides remaining on the mayor's staff since he first took office.

"There's never a good time to leave," Spielfogel said, "but we have a very strong team here and this seemed like the right juncture after five years to transition out."

Known as a policy wonk and strategist, Spielfogel advised Emanuel on rolling out various initiatives, from the pursuit of the Lucas Museum of Narrative Art and Barack Obama Presidential Center to the city's new ride-sharing ordinance and a minimum wage increase. Spielfogel has been a fixture in senior-level meetings, determining not just how to form the mayor's projects but also how to message them.

It's a focus he also had on both of Emanuel's mayoral campaigns.

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