It can be difficult to recall that Sari Gueron made her name three years ago by designing elegant cocktail dresses with a distinctly 10021 slant. Perhaps it's because in her last two Spring collections, the designer has let her bohemian side shine through—especially in her standout show of 12 months ago, with its ethereal cotton dresses (styled with Birkenstocks, no less). With her latest collection, however, Gueron struck a wonderfully coherent balance. Like many designers who have tired of overly girlish frocks, she was hungry for a bit of grown-up polish. "I wanted everything to be a little chicer, a little sexier," she explained before her show.

Gueron accomplished both in her first three looks, a primary-hued series of dresses with elegant gathered necklines and gently nipped waists that were short enough to be sexy but, in a great silk-cotton, maintained a casual attitude. That push-and-pull was evident throughout the show. Daytime looks that spoke to Gueron's love of the ad hoc, utilitarian garb that artists sport in their studios—such as linen shifts with patch pockets or baggy, rolled pants topped with a bright smock—were all neatly refined, despite their slightly sloppy origins. As for evening, a belted black chiffon dress with a touch of beading had all the ease of a T-shirt, and made you wonder why anyone would bother with the corset numbers that followed.