In 2007, Martin Heidegger's Gedachtes appeared, as volume 81 of the Gesamtausgabe. It contained more than five hundred poems (or, more accurately, texts that may be read as poems), and represented a considerable extension to a small but significant body of poetic work that had already appeared in earlier volumes. These poems were written at important and, occasionally, at critical points throughout his life and career, and they clearly performed a function that was both intellectual and personal. This article argues that these texts form an essential part of Heidegger's oeuvre, and that they offer new insights into his philosophy and into his continuing struggle to find a language appropriate for developments within that philosophy. Heidegger's poems are, however, far from being simply literary refashionings of philosophical ideas. In their subtle use of poetic form, their modulation of image and symbol and in their control of mood and diction, they stand for themselves as important moments within the canon of the twentieth-century German lyric.