A soloist at the Grand Theatre/National Opera in Warsaw. She studied at the Warsaw Academy of Music, graduated with honours and won a Kazimierz Czekotowski Award. Still as a student, she made her debut at the Grand Theatre in Warsaw, where she was engaged after her graduation. She appears in numerous operas, e.g. Roksana in King Roger by Szymanowski, Micaela in Carmen, Nedda in I Pagliacci, Pamina in The Magic Flute, the Countess in Le Nozze di Figaro, Mimi and Musetta in La Boheme, Liú in Turandot, Hanna in Straszny Dwor (The Haunted Manor) by Moniuszko, Elvira in Ernani, Violetta in La Traviata, Eve in The Paradise Lost, Maria in Mazepa. Her repertoire includes songs, oratorios and cantatas (soprano parts in Stabat Mater by Pergolesi, Mass in C Minor by Mozart, Requiem by Verdi, Magnificat by Bach, Dies Irae by Penderecki, The 9th Symphony and the oratorio Christ on the Mount of Olives by Beethoven, the 2nd Symphony "Lobgesang" by Mendelssohn, the Symphonies No. 2, 4, 7 by Mahler). She has made many recordings and her arias performed for Polish Radio were named as Best Recording of 1990.
Izabella Klosinska has recently enjoyed considerable international success. She has taken part in the concert version of Berlioz's Les Troyens at Concertgebouw in Amsterdam and in American productions of Szymanowski's Krol Roger in Buffalo and Detroit (Michigan Opera Theatre; spring 1992). In autumn 1992 she sang during the opening ceremony of the new opera season in Taegu, South Korea (La Traviata). In 1993 she took part in the American premiere of Dvorák's oratorio St. Ludmila at Carnegie Hall as well as in auditions and preparations for the title role in Dvorák's Rusalka at the Metropolitan Opera. At that time she also sang Liú in Turandot in the Seul Opera. In September 1992 she appeared at the Music Festival in Maastricht in the 3rd Symphony by Gorecki (the same part sung at the Alicante Festival in 1995 and in Madrid and Cordoba in 1996). In December 1995 she appeared in the concert recording of Deborah by Jaele Pizetti with the Concertgebouw Orchestra in Amsterdam. I. Klosinska is also a frequent guest at the Warsaw National Philharmonic.