By the 1880's, the Square had become the center of a fashionable residential district. Three prominent churches faced into the square - Calvary Presbyterian, Congregational and Trinity Churches. The imposing 90 foot high Corinthian granite column was raised in the center of Union Square in 1903, and dedicated by President Roosevelt that same year. It is crowned with a bronze goddess of Victory, sculpted by Robert Aitken, who modeled it after the young Alma de Brettville Spreckels.

By the turn of the century, offices and stores gradually squeezed out the residences and churches surrounding the Square. After the 1906 earthquake, Union Square became the center of San Francisco 's premiere shopping district. Union Square 's present character was established by the construction of the Hotel Saint Francis in 1908. It was, and remains the tallest structure (13 stories) facing the Square, forming an impressive backdrop for the Dewey Monument . Over the years, the park was redesigned many times, but always followed the natural topography of the area, a sloping bowl-shaped space, allowing visual access throughout the whole park from the surrounding sidewalks.

With the population explosion in San Francisco in the 1930's and the vast number of automobiles coming into the downtown area, parking in this fashionable shopping district became increasingly difficult. Businesses surrounding the Square worried that they would lose customers due to the lack of parking. The Union Square Garage Corporation was formed and lobbied for years for permission to build the world's first underground parking structure. After going all the way to the California Supreme Court for a decision as to whether the City could lease the land under a public space to a private corporation, permission was finally granted. Three years of research and design followed, and on May 31, 1941 , ground was finally broken for the garage and the square as it existed until recently.

In 1997 the San Francisco Prize Coalition and the City of San Francisco announced an open competition for the redesign of Union Square Park . Called Toward a More Perfect Union: An International Design Competition for the Future of Union Square , the competition received 309 entries from 10 countries and 20 states. The winning entry entitled "All the Square is a Stage" sought to transform the Park from an imposing, seldom used urban space into an inviting oasis that would be used by all the inhabitants surrounding the area. The design is notable for its easy access, a café with lots of open-air seating, and an orchestra-sized stage, as well as the return of the signature palms to the four entrances of the Square.

A "new" Union Square opened to the public on July 25, 2002 , following 3 years of planning and 18 months of construction and illustrating a successful public/private partnership. The $25 million project, designed by Philips + Fotheringham Partnership, Landscape Architects, renovates Union Square and the Parking Garage to improve their relationship with the street and to make Union Square more accessible and a more fitting complement to today's public and commercial uses. Originally a park surrounded by churches and residences, the Union Square of today is the commercial retail center of the City. The square continues to serve as a stage for gatherings of all types, including musical performances, dances, art exhibitions, rallies and spontaneous outbursts of theater, speech, and song.

The new design improves visibility into the square, making it more inviting and accessible. It provides flexibility to accommodate a wide variety of activities, a place that facilitates interaction between individuals and groups, new pedestrian amenities and new public art by R.M. Fischer . Plaques highlighting significant milestones in the Square's history decorate two entrances.

The design includes a large central plaza, stage lawn terraces to Geary Street , terraced steps aligned with Maiden Lane and four grand corner entrance plazas. A ticketing pavilion and a café with outdoor seating are included in the project. The historic Dewey Monument is retained, as are signature palms at the four corner entrances to the Square .