As the Spring 2012 runways would have it, strong lines and structured edges took shape — quite literally. From bright psychedelic patterns at Milly and art deco references at Gucci, to boxy silhouettes at Christian Dior and graphic prints at Carolina Herrera, not only are designers in a geometric state of mind, but celebs like Nicole Richie and Rooney Mara are breathing life into the trend in supercool ways. To don this bold style, try it on in doses. A mod prism clutch, a Mondrian-inspired pendant necklace, a square stack of bangles, or a geo-cut pair of heels should give your finished look the right blend of shapeliness and symmetry. Pair any of our editors' picks below with your favorite jeans and a casual topper, and your off-duty festival look is ready to go. Shop your favorites — and let us know how you'll be wearing Spring's geometric pieces.