Madrid is a late-night city. You’ve probably heard that the Spanish are notorious for eating late, but you might not know that the museums are open late too. During a short trip to Madrid for the ARCO art fair, I found myself at the Museo Nacional Centro de Arte Reina Sofia until 9 p.m. most nights, waiting for dinner to start and trying to keep my feet steady walking through the museum’s endless rooms. The first night, jet-lagged but art-hungry, I attended the opening of an exhibition of the work of Hans Haacke, the German-born American artist known primarily for his institutional critiques bordering on investigative journalism. If you wade through Hans Haacke’s long exhibition history, you find a shortlist of the most important art exhibitions of the last 45 years: Earth Art (1969); Live in Your Head: When Attitudes Become Form (1969); Documenta 5 (1972); Magiciens de la terre (1989); Image World: Art and Media Culture (1989); Documenta X (1997); and Beyond Geometry: Experiments in Form 1940s–1970s (2004), not to mention the Venice Biennales. I realized that outside of gallery presentations, I had never seen a major show of Haacke’s in the U.S., and that’s because there hasn’t been one. Recognizing my good fortune, I switched shoes, forgot about dinner, and dug in.