The James R. Thompson Center, under reconstruction as Google Center or Googleplex Chicago and originally the State of Illinois Center, is a postmodern-style building designed by architect Helmut Jahn, located at 100 W. Randolph Street in the Loop district of Chicago. Designed around a post-modernist rotunda, it was built to house offices of the Illinois stat…The James R. Thompson Center, under reconstruction as Google Center or Googleplex Chicago and originally the State of Illinois Center, is a postmodern-style building designed by architect Helmut Jahn, located at 100 W. Randolph Street in the Loop district of Chicago. Designed around a post-modernist rotunda, it was built to house offices of the Illinois state government in the most populated city and county of the state and opened in 1985. In 2022, state government offices were relocated nearby to less costly quarters. Internet company Google purchased the building from the state and expects to move in 2026, after two years and $280 million of renovations.