Viktor Ullmann’s vocal compositions are exceptional works of art that were forgotten for decades and are infrequently performed in North America. Ullmann (1898-1944) developed his mature compositional style during his two-year imprisonment in the Nazi ghetto of Theresienstadt. A student of Arnold Schoenberg’s Second Viennese School and Alois Hába at the Prague Conservatory, Ullmann developed his own compositional style that featured a prolific use of motivic material, a balance of tonality and atonality, the importance of the natural-harmonic-series, careful prosody settings, the use of dynamics to increase tension, overlapping phrase structure, the use of polyphonic texture including imitation and canonic techniques, and equality between the vocal line and the accompaniment. As a composer of vocal music, Ullmann’s understanding of the potential difficulties experienced by singers of twentieth-century compositions is clear. He composed quality pieces that deserve to be performed and are excellent additions to the classical canon regardless of their compositional circumstances. The quality of these works is demonstrated in Ullmann’s choice of setting lauded poets and poems, the performance of his works by noted singers and opera companies, and the wide acceptance of these pieces by international audiences. Ullmann’s oeuvre is an important link in the chain of western art music tradition. This guide provides singers and teachers of singing with the necessary information for the successful performance of Ullmann’s Theresienstadt-period works (1942-44) that are appropriate for a mezzo-soprano. Chapter 1 provides an explanation of the research, analytical methods, and processes for this guide. A short biography of Ullmann, in chapter 2, follows his growth as composer, conductor, music critic and journalist, pianist, and teacher, including his imprisonment in Theresienstadt. Chapters 3 and 4 of this guide provide specific information for the successful performance of Drei jiddische Lieder (Březulinka) (Three Yiddish Songs (Birch)), op. 53; Drei chinesische Lieder (Three Chinese Songs); Immer inmitten, Solo-Kantate nach Gedichten von Hans Günther Adler (Always in the Midst, Solo Cantata with Poetry by Hans Günther Adler); Lieder der Tröstung (Songs of Consolation); “Herbst” (Autumn); and “Arie des Trommlers” (The Drummer’s Aria) from Der Kaiser von Atlantis oder Die Tod Verweigerung (The Emperor of Atlantis or Death’s Refusal), op. 49. The final chapter presents suggestions for further research and concludes the guide. The appendices contain International Phonetic Alphabet (IPA) transcriptions, English translations, and a list of works that pair well in recital with the compositions discussed in this guide. The availability of Ullmann’s scores by Schott make his works readily accessible for performance in recital.