Martha Diamond (1944-2023) was among the most perceptive painters of the last five decades. Her work's formal concision and painterly bravado reflect an inner dialogue with generations of abstract artists, while her singular vision spotlighted her architectural and compositional fascinations. Comprising paintings, monotypes and other works on paper, this focused survey of Diamond's career proposes "deep time" as a new way of understanding her contribution to American painting. It emphasizes her unswerving commitment to capturing the emotional character of built space, tracking throughlines across mediums and methods to reveal a process that combines spirited experimentation with perceptive observation. Deep Time features rarely seen pieces: from the little-known "single-picture" images of the 1970s and the vertiginous paintings of her native New York City during the 1980s, '90s and '00s to the vivid abstractions that increasingly characterized her later work.