Elie Saab Spring, Marc by Marc Jacobs; both Spring 2011
Matthew Williamson, Jenni Kayne; both Resort 2011
Derek Lam, Resort 2011; Tory Burch, Spring 2011
Why does it work? The same reason wearing black head to toe works - it's flattering. And by keeping your pink a pale nude and your red a poppy orange, the contrast is high enough to allow viewers to distinguish you from a Valentine's day card.