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

HILARY DUFF

Last year, Duff, then 17, hadn't left her teen-queen roots behind (left). Today, the singer-actress (in Zac Posen, center, and Alessandro dell'Acqua) looks every inch the young mogul she is. "She's gone from being overaccessorized to simplifying and letting her own personality stand out, rather than layering herself in thousands of necklaces and bangles," says Kaufman.