Channeling Catherine: Her haute couture version of tuxedo style.
Dashing and legendary designer on your arm and on your label: Desirable.
Cole Haan peep-toe heels at Zappos.com: Staple.
Girls-will-be-boys sexy tuxedo with satin lapels: Necessary.
Vogue Paris Original 2360, designed by Yves Saint Laurent, copyright 1999: Must.