Rock Witchu Tour was the fifth concert tour by American singer Janet Jackson, in support of her tenth studio album Discipline (2008), and her first in nearly seven years, following a total blacklist of the singer's music, due to the Super Bowl XXXVIII halftime show controversy. The tour began on September 10, 2008, in Vancouver, Canada, and was scheduled to conclude in Fukuoka, Japan, on February 22, 2009. However, several North American dates were cancelled due to Jackson's vertigo, and the upcoming Japanese leg was scrapped, following the 2009 economic crisis and another bout of illness for the singer. The tour officially ended on November 1, 2008, in New York City, resulting in only sixteen shows. Still, the tour received rave reviews, and at the end of 2008, was placed 78th on Pollstar's "Top 100 North American Tours", grossing $11.7 million.

After releasing her eighth studio album, Damita Jo (2004), Janet dealt with criticism with the massively controversial Super Bowl incident, resulting to a blacklist of Jackson's subsequent singles and music videos from several conglomerates, including Viacom's MTV and CBS and various subsidiaries, which largely affected Jackson's airplay on many radio formats and music channels worldwide. Due to that, Jackson did not go on tour to support Damita Jo, and instead recorded her ninth studio album during 2005–2006. The album, entitled 20 Y.O., was released in September 2006, and it was announced that Janet was prepping a worldwide tour to promote the album. However, the unnamed tours were canceled abruptly when Jackson began recording new material. Jackson stated:

"I was supposed to go on tour with the last album [...] We were actually in full-blown tour rehearsals at that point ... learning numbers, getting everything together, set designs [...] I had to kind of shut everything down and go into the studio."

In early 2008 on The Ellen DeGeneres Show, Jackson announced that she would go on tour. The audience was given free tickets to her show at the Staples Center. While planning the tour, Jackson started a phone line where fans could call in and request songs to be performed. Jackson was set to perform all of her memorable hits, including those from her pre-Control days.

According to Janet herself, "It will definitely be a big production but it will definitely also be something that I've never done before, that people have never seen from me before." The title of the tour, "Rock Witchu Tour", was named for a song of the same name on her latest album, Discipline. The tour was set to be worldwide, with Janet stating, "It's been a while so I really want to make my rounds. I haven't been to Australia in a very long time; I can't wait to go there. There are a lot of places where I really want to stop off at, and that's the idea, that's the goal with this tour."

In April 2008, the singer claimed, "I'm still promoting the new album (Discipline) right now, but we'll be getting into rehearsals in about a month and then start touring," Jackson says. For Janet, "My true goal is to try at least do every single that I’ve ever had. So, I’ve got to figure out a way to fit this in two hours, and yet give them enough of each song so that they don’t feel hungry for more of that song in particular." The two and a half hour show kicked off in Vancouver on September 10, 2008, to rave reviews.

For two hours, the show sees Janet performing nearly 40 hits, complete with theatrics, costume changes and a few surprises. According to Janet, the tour features a set list that was directly influenced by her fans. The setup of the stage includes a giant square-shaped catwalk surrounding the first several front rows of seats, reaching out to the center of the arena where fans could see Jackson from any level of seating. Rows of seating inside the catwalk were exclusively designed for those with purchased fan club memberships. There are three video screens that take on the stage, including the biggest one being in the center where video clips are shown throughout songs to take place for effects and in-between costume change breaks. Other special staging includes movable staircases, steel cages, pyrotechnics, and other special pieces.

The show begins with an echo of words being said in the distance of the arena, such as "Janet", "Rock Witchu", "Dance", and "Discipline". As the words speed up, the show lights come on and several dancers dressed as astronauts appear on the stage, with two standing beside two big glittery "J"'s (representing Janet's name.) The "J"'s move back and forth on the center of the stage with stars appearing on the center video screen (a representation of Space). Pretty soon, fog appears in front of the audience and a bang of pyrotechnics blasts, thus beginning the opening of the show. Jackson appears on the upper center section of the stage in a gold hyperspace dance suit singing "The Pleasure Principle", as well as "Control", when 13 dancers join her, emerging from underground in various positions around the massive stage, and "What Have You Done for Me Lately", on the "Control Medley", and later moving on to "Feedback". She then performed "You Want This", "Alright" and "Miss You Much." Afterward Janet did a brief costume change and returned to the stage in a sultry red dress to perform a string of ballads including "Come Back to Me", "Again" and "Let's Wait Awhile." After another wardrobe change, she came back out to perform a mixture of old and new songs including "So Excited", "Together Again", "Nasty", "Escapade", "That's the Way Love Goes", "Luv" and "Rhythm Nation".