For more than a dozen years, John Kissinger served as CEO of GRAEF, building both Milwaukee's skyline and the firm, which is one of the largest engineering architecture firms in the country.

A structural engineer by training, Kissinger joined GRAEF after earning his bachelor's degree from the University of Wisconsin-Milwaukee and master's from UW-Madison. His first professional job: designing smokestacks for power plants — structures that "were really a lot more elaborate than you might think outside."

Now, after four decades with the Milwaukee-based firm, he has retired, leaving behind a legacy that includes landmark structures like the addition to the Milwaukee Art Museum, the Santiago Calatrava-designed structure whose soaring wings have become a symbol of the city.