Dever made her Metropolitan Opera debut in 1994, as Amneris in Aida. Other roles at the Met include Azucena in Il Trovatore, Ulrica in Un Ballo in Maschera, Eboli in Don Carlo, and Fricka in Die Walküre (1993 Japan tour under James Levine).
She has sung at the Washington Opera, New National Theater (Tokyo), Michigan Opera Theatre, Teatro Lirico di Cagliari, Teatro Massimo (Palermo; Grand Reopening), Teatro alla Scala in Milan, Vienna State Opera, Deutsche Oper in Berlin, Teatro Colón, Arena di Verona and the Cincinnati Opera.
Dever's performances have taken her to Montreal, Mexico City, Macerata, Parma, Reykjavik, San Diego, Antwerp, Puerto Rico, Palermo, Vancouver, Santiago, Berlin, and Buenos Aires,
She has performed with the State Symphony Orchestra of Sao Paulo, the Louisville Orchestra at Chautauqua, the Florida Philharmonic, the Israel Philharmonic Orchestra, the Pacific Symphony, the Netherlands Radio Orchestra and the National Orchestra of Mexico.
Dever sang at a Lincoln Center live concert telecast with Luciano Pavarotti (Pavarotti Plus, Great Performances). She performed the role of Dalila opposite Placido Domingo's Samson in 1998 (Mexico City).