A comprehensive theory of half‐diminished seventh chord usages recognises the potential of the chord's outer pitches to move in one of four ways: wedging inward, wedging outward, with the root as the common tone or with the seventh as the common tone. Typical destination chords are major and minor triads but can also be seventh chords, as in the opening phrase of Wagner's Prelude to Act 1 of Tristan und Isolde. Examples from the music of Berlioz, Brahms, Chopin, Debussy, Dvořák, Grieg, Liszt, Tchaikovsky, Richard Strauss and Wagner demonstrate the full range of possibilities and some artistic contexts. Extended implementations of half‐diminished harmonies include the Finale of Tchaikovsky's Sixth Symphony, the interlude between Scenes 2 and 3 of Act 1 of Wagner's Götterdämmerung and Debussy's Pelléas et Mélisande.