2007–2011: Good Music era and name change
On November 7, 2007, Bey performed live in San Francisco at The Mezzanine venue. The performance was recorded for an upcoming "Live in Concert" DVD. During the event, he announced that he would be releasing a new album, The Ecstatic. He performed a number of new tracks; in later shows, he previewed tracks produced by Madlib and was rumored to be going to Kanye West for new material. Producer and fellow Def Poet Al Be Back revealed he would be producing on the album as well. The album was released on June 9, 2009; but only Madlib's production had made the cut, along with tracks by Preservation, The Neptunes, Mr. Flash, Madlib's brother Oh No, J. Dilla, and Georgia Anne Muldrow.
Bey appears alongside Kanye West on the track "Two Words" from The College Dropout album, the track "Drunk and Hot Girls" and the bonus track "Good Night" off West's third major album, Graduation. In 2002, he released the 12" single Fine, which was produced by West and featured on the Brown Sugar soundtrack.
In 2007, Bey appeared on Stephen Marley's debut album Mind Control on the song "Hey Baby". He also appeared on the debut album from Apollo Heights on a track titled "Concern". That October, he signed a deal with Downtown Records and appeared on a remix to the song "D.A.N.C.E." by Justice.
In April 2008, he appeared on the title track for a new album by The Roots titled Rising Down. The single, "Life In Marvelous Times", was made officially available through iTunes on November 4, 2008, and was also available for stream on the Roots' website Okayplayer.
In 2009, he worked with Somali-Canadian rapper K'naan to produce the track "America" for K'naan's album Troubadour.
In April 2009, Bey traveled to South Africa for the first time, and performed with The Robert Glasper Experiment at the renowned Cape Town International Jazz Festival. He treated the South African audience with an encore, introduced by his own rendition of John Coltrane's A Love Supreme, followed by a sneak preview of the track "M.D. (Doctor)".
Bey has designed two pairs of limited edition Converse shoes. The shoes were released through Foot Locker stores on August 1, 2009, in limited amounts.
In late 2009, he created his own clothing line with the "UNDRCRWN" brand called the "Mos Def Cut & Sew Collection". The items were released in select U.S. stores and almost exclusively on the UNDRCRWN website. That year, he was among the MCs aligned with American entrepreneur Damon Dash's DD172 and collaborating with American blues rock band the Black Keys on the Blakroc album, a project headed by the Black Keys and Damon Dash. Bey appeared with Harlem-bred rapper Jim Jones and the Black Keys on the Late Show with David Letterman to perform the Blakroc track "Ain't Nothing Like You (Hoochie Coo)".
In 2010, Bey featured on the first single, "Stylo", from the third Gorillaz album, Plastic Beach, alongside soul legend Bobby Womack. He also appeared on the track titled "Sweepstakes". In March 2010, Bey's song "Quiet Dog Bite Hard" was featured in Palm's "Life moves fast. Don't miss a thing." campaign.
In September 2010, after appearing on Kanye West's G.O.O.D. Friday track "Lord Lord Lord", Bey confirmed he had signed with GOOD Music. Bey has been an active contributor to the recovery of the oil spill in the Gulf, performing concerts and raising money towards repairing its damages. In June 2010, he recorded a cover of the classic New Orleans song originally by Smokey Johnson, "It Ain't My Fault" with the Preservation Hall Jazz Band, Lenny Kravitz and Trombone Shorty.
In September 2011, the rapper announced that he legally changed his name to Yasiin Bey and would go by that name, retiring his Mos Def moniker (short for "Most Definitely"). Bey told a reporter "I began to fear that Mos Def was being treated as a product, not a person, so I’ve been going by Yasiin since ’99. At first it was just for friends and family, but now I'm declaring it openly." Bey also stated "Mos Def is a name that I built and cultivated over the years, it's a name that the streets taught me, a figure of speech that was given to me by the culture and by my environment, and I feel I've done quite a bit with that name. ...it's time to expand and move on." Yasiin is a name in the Qur'an's 36th surah and was important to the rapper who converted to Islam in his teens. Bey said the name change would eliminate "having any moniker or separation between the self that I see and know myself as."
Shortly after the name change announcement, Bey recorded as the narrator of the children's hip-hop musical, Pacha's Pajamas: A Story Written By Nature.
