10 Most Stylish Stars

From the always chic Nicole Richie to the much improved Ashlee Simpson – check out the top fashion icons of 2005, as selected by PEOPLE style expert Susan Kaufman. By Emily Fromm

ASHLEE SIMPSON

Jessica's little sis is all grown up, having traded last year's '80's-inspired getups (left) for streamlined jeans-and-blazer combos (center) and designers such as Giambatista Valli. "She's showing off her body, wearing heels," says Kaufman of Ashlee's improved look. "She's just becoming more comfortable in her own skin."