Train's voice is husky, rich and dark with a big range and maturity of style that belies her age... She's confident – and with good reason.

[16] The album, where she collaborated mainly with Ed Harcourt, Cherry Ghost's Simon Aldred, and Martin Craft,[4] features "Train's dreamy, intense and intoxicating Southern American vocals.

[24] Train often plays with the band Scrapomatic and contributed vocals, violin, and songwriting on their 2006 album Alligator Love Cry, under the name of Kristina Beaty.

[27] Train performed at the T.J Martell Foundation 34th Annual Awards Gala alongside Willie Nelson, Dianne Reeves, and Wynton Marsalis on October 28, 2009.

The band included musicians Lionel Loueke, Vinnie Colaiuta, James Genus, Pino Palladino, Tal Wilkenfeld, Greg Phillinganes, and Trevor Lawrence Jr.

Train performed at the bi-coastal 70th birthday celebration for Herbie Hancock which took place at New York's Carnegie Hall and Los Angeles' Hollywood Bowl alongside Wayne Shorter, Ron Carter, Jack DeJohnette, Dave Holland, Joe Lovano, Terence Blanchard, Wallace Roney, Zakir Hussain, Esperanza Spalding, Derek Trucks, Susan Tedeschi, Lisa Hannigan, Alex Acuña, Paulinho Da Costa, Juanes, Niladri Kumar, Bill Cosby, and Tavis Smiley.

Train co-wrote the closing track Salvation on Robert Randolph and the Family Band's album We Walk This Road which was produced by T-Bone Burnett.

[30] On December 11, 2010, Train performed with Herbie Hancock, India.Arie, Florence and the Machine, Robyn, Colbie Caillat, and Barry Manilow at the Nobel Peace Prize Concert hosted by Denzel Washington and Anne Hathaway in Oslo, Norway.

[35] Train is the voice of the Lexus Amazing in Motion 2013 global campaign, singing the song I'm Wandering previously released by Jackie Wilson (1958) and Aretha Franklin (1962).

[36] Kristina Train sang the songs "When the Shy Star" and "Sleep Now" (with Julian Lennon) on the album Goldenhair by Brian Byrne released in 2017.