This month's street style roundup, courtesy of photographer Adam Katz Sinding of Le 21eme, is dedicated to fashion's head cases--literally! Trendsetters around the globe are topping off their winter friendly ensembles with an assortment of chic chapeaux--everything from slouchy knit caps to boyish bowlers and short-brim fedoras--and the results are truly inspiring. Scroll thought today's slideshow to see all of our favorite hat-centric looks and shop similar styles.