The Shamrock Bar & Grille is one of Madison's most long-lived LGBT bars. Just a block off the Capitol square, The Shamrock has been the only downtown gay/lesbian bar during much of its lifetime. (During its early years the Cardinal Bar about 10 blocks away was its nearby competition, although the stronger contenders were farther away: Rod's, and later Club 5.)

There was for some time either strong local competition or a blessing with another LGBT bar two doors away. Initially there was R Place opened in 1996, which quickly became Scandals after a scandal involving the R Place owner. Next was Kirby's Klub. After that came the Rainbow Room (1999-2003).

The newcomer bar to the area has been WOOF's on King Street, which opened in 2008.

Upon entering the Shamrock, in the front room were a long bar along the left (east) wall, and on the right (west) wall were lined about 6-8 tables with stools, with a pool table near the back of this room. Just at the front was a large screen TV, great for watching Badgers games and other events. Moving toward the back, rest rooms were on the left (the men's room was long and narrow, one couldn't help but bump up against another person). Farthest back through a doorway was another smaller but more intimate bar, and a rear exit. (In fall 2006, the rest rooms and back bar were undergoing renovation.)

Throughout its lifetime, the Shamrock has been both a friendly place for a drink, and a great place to get an excellent burger, sandwich, or fries from the grill. Both Friday Fish Fry and Sunday Brunches were also very popular. The staff was always friendly, and the Irish owner for much of its time was well known for dressing up on occasion.

While the bar originally opened as "Shamrock Bar and Grill", it was renamed as Phaze II in December 1991, with the same owner, J.J. O'Connell. But in September 1994 the "Phaze II" name was quietly dropped and the original "Shamrock" name restored, without explanation-- and so it remained. The LGBT destination Shamrock Bar & Grille is still open as of late 2022.