Best Celebrity Style For September 19, 2011

Between the Fashion Week craziness, celebrities are suiting up in style for their respective red-carpet outings and parties. In light of Fall, we're seeing a return to trousers, slick suiting, and layers, though, of course, there are a few sweet shifts and colored frocks — we're looking at you Kate Bosworth and Zoe Saldana — to capitalize on the last of the warmer weather. Click through to get a glimpse of this week's standouts, from Madewell's It girl, Alexa Chung, to hot mama-to-be Beyoncé — there's plenty of inspiring style in store.