An active chamber musician, her collaborators include Nemanja Radulović, Andreas Ottensamer, , Goldmund Quartet, Camille Thomas, Tine Thing Helseth, Juan Diego Flórez and Nicola Benedetti. Ksenija is a regular guest performer at the Ravinia, Cheltenham, Mostly Mozart, Schleswig-Holstein, MISA, Gstaad Menuhin, MITO, Verbier and Rheingau music festivals. This season, Sidorova performs recitals with baritone Thomas Hampson in Tonhalle Zurich, Beethovenhaus Bonn and Amsterdam Concertgebouw, as well as recitals with Avi Avital, and the Signum Saxophone Quartet. 

Her latest release Crossroads (Alpha, 2024) features Chaconne by Sergey Akhunov, alongside J.S. Bach D minor concerto, Dobrinka Tabakova’s Horizons and Gabriela Montero’s Beyond Bach. Her album Piazzolla Reflections (Alpha, 2021), was acclaimed as ​“brilliantly played [and] beautifully recorded” (Gramophone), numbered among the best new classical albums of the year (Classic Review), and was named BR Klassik’s album of the month. This follows previous successful releases: Arturs Maskats’ accordion concerto (Ondine, 2023) with the Latvian National Symphony Orchestra and Andris Poga; Classical Accordion (Champs Hill Records, 2011); Fairy Tales (Champs Hill Records, 2013) recorded with BBC National Orchestra of Wales/​Rundell; and Carmen (Deutsche Grammophon, 2016) for which she won the ECHO prize for Instrumentalist of the Year in 2017. 

Encouraged by her grandmother, herself steeped in the folk tradition of accordion playing, Ksenija started to play the instrument at the age of six under the guidance of Marija Gasele in her hometown of Riga. Her unfettered interest in classical and contemporary repertoire took her to the Royal Academy of Music, London, where she became a prize-winning undergraduate and postgraduate studying under Owen Murray. In May 2012, she became the first International Award winner of the Bryn Terfel Foundation and appeared at the Royal Albert Hall in October 2015 as part of his 50^th birthday celebrations, alongside Sting. She is a recipient of Philharmonia Orchestra’s Martin Musical Scholarship and Friends of the Philharmonia Award, as well as the Worshipful Company of Musicians Silver Medal. Ksenija has been an Associate of the Royal Academy of Music since 2016 and was made a Fellow (FRAM) in 2021.