The state of Texas sought to address the intensifying shortage of space in the old capitol building in Austin, deciding that a new office wing should be added. The logical place for an addition was the plaza immediately to the north; however, a large building there would have eliminated the historic north facade and covered what had traditionally been seen as an important public space. Instead, an expansion to the capitol was built under the north plaza, connecting to the existing capital underground.
In 1993, the $75 million, four-story, underground Capitol Extension was completed to the north, doubling the square footage available to Capitol occupants and providing much improved functionality. Though the extension encompasses 667,000 square feet (62,000 m2) (nearly twice the floor space of the original building), there is little evidence of such a large structure at ground level, except for extensive skylights camouflaged as planter rows, and the four-story open-air inverted rotunda.
In 1995, a comprehensive interior and exterior restoration of the original building was completed at a cost of approximately $98 million. Finally, in 1997, the park-like grounds surrounding the Capitol received an $8 million renovation and restoration.