Derek Mahon, like many writers of ekphrastic poetry, uses the interartistic encounter as an opportunity to meditate on his own aesthetic practice. While the self-reflexive dimensions of Mahon's ekphrases have received considerable critical attention, the implications of his choice of source material remain underexamined. Many of Mahon's ekphrases respond not simply to paintings, but to works depicting three-dimensional objects and architectural spaces: indeed, he sometimes treats rooms and things as though they were the art objects in question. This is the case in a variety of poems, from “Courtyards in Delft” and “The Studio,” to later ekphrases like “Studio in Antibes,” and “New Space.” As these titles suggest, many of the objects and spaces he chooses are used in the production of further artworks—some of his best-known material ekphrases are responses to artists' rooms. This predilection repays critical attention, as the materiality of Mahon's ekphrastic writing shapes its metapoetic work in significant ways. Many of Mahon's aesthetic reflections concern abstraction, materiality, craft, and making, and these concerns take on additional complexity when the ekphrastic sources themselves involve physical things. Most importantly, Mahon's material ekphrases shed light on some of the ambivalence and ambiguity attending his aesthetic ideals.