Allyson continued issuing albums at a steady pace throughout the remainder of the decade, including such titles as 1993's Sweet Home Cookin' and 1994's Azure-Té, plus a pair in 1996, Collage and Daydream. For her final release of the '90s, 1999's From Paris to Rio, Allyson decided to try something different and issued an album in which she sang lyrics in French and Portuguese, while covering a lot of ground stylistically (everything from a Jacques Brel cover to samba and bossa nova tunes). Allyson's next offering, 2001's Ballads: Remembering John Coltrane, proved to be one of the most acclaimed and successful of her entire career, as it earned a pair of Grammy nominations. For 2002's In Blue, Allyson opted to cover other artists' material (Mose Allison, Joni Mitchell, George and Ira Gershwin, Blossom Dearie, Abbey Lincoln, Oscar Brown, Jr., and Bonnie Raitt), as the singer only penned one of the album's 13 tracks, a path she also followed two years later on Wild for You, which contained her versions of songs from artists she had grown up with, like Cat Stevens, James Taylor, and Mitchell. In 2006 she released Footprints, earning herself a Grammy nomination for Best Jazz Vocal Album.
Over the years, Allyson has performed at some of the top concert halls in the U.S., including an all-star tribute to Ella Fitzgerald at New York's Carnegie Hall, in addition to playing alongside both the Kansas City and Omaha symphonies. In 2008 Allyson released Imagina: Songs of Brasil, interpreting the songs of Antonio Carlos Jobim, Edú Lobo, Torquato Neto, and Pedro Caetano. She toured the recording for the next year before taking a break. In 2010 she began recording collection of jazz, pop, and Broadway standards entitled 'Round Midnight, where she cut tunes by everyone from Duke Ellington and Stephen Sondheim to Paul Simon and Bill Evans. The album marked the first time in her recording career that she played all the keyboards on the set. It was issued in 2011 by Concord Jazz. ~ Scott Yanow & Greg Prato, Rovi