There’s only one problem with our favorite underdog: Ukraine’s economy remains badly pock-marked by corruption and graft. No amount of aid—including a $1 billion loan guarantee package from the U.S. – will help the country if it doesn’t clean out its own closets. According to global corruption ratings, Ukraine is worse even than Russia.

Penny Pritzker delivered that tough love message in Kiev, the city of her great grandfather’s birth, last week. “President [Petro] Poroshenko said the right things,” the Commerce Secretary, referring to his promise to adopt economic reforms, told me when she returned Friday after stops in Poland and Turkey. “But do they have the will?” That, of course, is a very different question.

Pritzker’s visit may have provided Poroshenko with useful political cover against vested interests protecting the status quo; two of three anti-corruption measures he introduced passed the Parliament. But that’s just a start.

For Pritzker, the visit packed an emotional punch. The Pritzker family fortune can be traced back to Kiev, where her great grandfather followed his brother’s escape from Tsarist Russia to the United States. The latter, Jewish and a political dissident, was about to be sent to Siberia.

Instead, the pair made it to the U.S. via Paris. Penny’s great-grandfather, Nicholas, earned nickels selling newspapers on the streets of Chicago before putting himself through law school and starting his own firm. His son Jay—together with Penny’s uncle and late father—would build the Hyatt hotel chain and one of Chicago’s great family fortunes (one that Penny herself helped expand, only to later dismantle in the face of an epic family battle.)

While she was in Kiev, Pritzker walked Maidan Square— the site of the brutal crackdown on protesters that led to the ousting of a Russian-backed president, followed by Russia’s annexation of Crimea. The Commerce Secretary listened to powerful political stories from the Ukrainians she met—but also heard troubling descriptions of widespread corruption from local entrepreneurs trying to start and run businesses.

Earlier this year, as I spent time with Pritzker and profiled her life, I was constantly struck by the resilience she showed in a tragedy-filled life. She’s remains relentlessly optimistic regardless of what has been comes her way. Pritzker’s attitude toward Ukraine’s economic prospects is no different: She told me, “As [Chicago Mayor] Rahm Emanuel says, don’t let a good crisis go to waste.”

Watch the 2014 Fortune Most Powerful Women Summit live stream on Wednesday, October 8, at 10:10am PT to watch Nina Easton interview Secretary Pritzker about Pritzker’s fascinating private life–and her public mission as Commerce Secretary.

“From the MPW Co-chairs” is a daily series where the editors who oversee the Fortune Most Powerful Women brand share their insights about women leaders.